diff --git a/qmake/builddir.pri b/qmake/builddir.pri
index 84c319a1e..9d1a3a2c3 100644
--- a/qmake/builddir.pri
+++ b/qmake/builddir.pri
@@ -12,21 +12,15 @@
 # "$$PWD/.." is the top of the source tree.
 #
 # clean_path() is used to clean the path.
-# It's not available on Qt 4.
-greaterThan(QT_MAJOR_VERSION, 4) {
-  TOP_SRCDIR = $$clean_path($$PWD/..)
-}
+TOP_SRCDIR = $$clean_path($$PWD/..)
 
-# In case absolute_path() doesn't return anything.
+# In case clean_path() doesn't return anything.
 isEmpty(TOP_SRCDIR) {
   TOP_SRCDIR = $$PWD/..
 }
 
 # shadowed() is used to retrieve the shadowed build path.
-# It's not available on Qt 4.
-greaterThan(QT_MAJOR_VERSION, 4) {
-  TOP_BUILDDIR = $$shadowed($$TOP_SRCDIR)
-}
+TOP_BUILDDIR = $$shadowed($$TOP_SRCDIR)
 
 # In case shadowed() doesn't return anything.
 isEmpty(TOP_BUILDDIR) {
diff --git a/qmake/compiler.pri b/qmake/compiler.pri
index 1dc60840e..47a8ea07f 100644
--- a/qmake/compiler.pri
+++ b/qmake/compiler.pri
@@ -23,18 +23,13 @@ QMAKE_RESOURCE_FLAGS += -compress 9
 # architecture of the compiler via the
 # force-x86_64-toolchain and force-x86-toolchain
 # CONFIG options. Because we have these, qmake's
-# QMAKE_TARGET.arch doesn't suffice any longer, and
+# QT_ARCH doesn't suffice any longer, and
 # we define MUMBLE_ARCH to be used in its place.
-MUMBLE_ARCH = $$QMAKE_TARGET.arch
-# When using Qt 5, use QT_ARCH instead of QMAKE_TARGET.
-# It also works for cross-builds.
-isEqual(QT_MAJOR_VERSION, 5) {
-	MUMBLE_ARCH = $$QT_ARCH
-	# QT_ARCH uses 'i386' instead of 'x86',
-	# so map that value back to what we expect.
-	equals(MUMBLE_ARCH, i386) {
-		MUMBLE_ARCH=x86
-	}
+MUMBLE_ARCH = $$QT_ARCH
+# QT_ARCH uses 'i386' instead of 'x86',
+# so map that value back to what we expect.
+equals(MUMBLE_ARCH, i386) {
+	MUMBLE_ARCH=x86
 }
 
 win32-g++ {
@@ -344,20 +339,7 @@ macx {
 	!CONFIG(universal) {
 		CONFIG += no-pch
 
-		# Qt 5.1 and greater want short-form OS X SDKs.
-		isEqual(QT_MAJOR_VERSION, 5) {
-			QMAKE_MAC_SDK = macosx
-		} else {
-			QMAKE_MAC_SDK = $$system(xcrun --sdk macosx --show-sdk-path 2>/dev/null)
-			isEmpty(QMAKE_MAC_SDK) {
-				QMAKE_MAC_SDK = $$system(xcode-select --print-path)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk
-				!exists($$QMAKE_MAC_SDK) {
-					message("Unable to find usable OS X SDK")
-					error("Aborting build")
-				}
-			}
-		}
-
+		QMAKE_MAC_SDK = macosx
 		QMAKE_CC = $$system(xcrun -find clang)
 		QMAKE_CXX = $$system(xcrun -find clang++)
 		QMAKE_LINK = $$system(xcrun -find clang++)
diff --git a/qmake/cplusplus.pri b/qmake/cplusplus.pri
index dbbe008ad..4e0ff3b4b 100644
--- a/qmake/cplusplus.pri
+++ b/qmake/cplusplus.pri
@@ -18,17 +18,13 @@
 # adds c++11, c++14 or c++1z to CONFIG. If none of
 # these are available, it adds c++03 to CONFIG.
 #
-# In Qt 5, qmake understands the c++11, c++14, and c++1z
+# qmake understands the c++11, c++14, and c++1z
 # CONFIG options, and will automatically populate
 # QMAKE_CXXFLAGS and QMAKE_LFLAGS with the appropriate
 # -std=c++XX values for the chosen C++ standard.
-# For Qt 4, this .pri files will add the proper flags,
-# because Qt 4's qmake doesn't know of the c++XX CONFIG
-# options.
 # 
-# The c++03 option is unknown for both Qt 4 and Qt 5.
-# We handle setting up the proper CXXFLAGS and LFLAGS for
-# both versions of Qt when c++03 is in CONFIG.
+# The c++03 option is unknown for Qt.
+# We handle setting up the proper CXXFLAGS and LFLAGS when c++03 is in CONFIG.
 
 # First, auto-populate CONFIG with the latest C++ standard
 # that Qt has detected support for.
@@ -78,26 +74,9 @@ CONFIG(c++14) {
 
 # Unix-specific handling of modern C++ features.
 unix {
-	# Qt 4, as opposed to Qt 5, doesn't automatically
-	# populate QMAKE_CXXFLAGS and QMAKE_LFLAGS with the
-	# appropriate -std=c++XX flags. So, for Qt 4, we'll
-	# have to set them up manually.
-	lessThan(QT_MAJOR_VERSION, 5) {
-		CONFIG(c++1z) {
-			QMAKE_CXXFLAGS += -std=c++1z
-			QMAKE_LFLAGS += -std=c++1z
-		} else:CONFIG(c++14) {
-			QMAKE_CXXFLAGS += -std=c++14
-			QMAKE_LFLAGS += -std=c++14
-		} else:CONFIG(c++11) {
-			QMAKE_CXXFLAGS += -std=c++11
-			QMAKE_LFLAGS += -std=c++11
-		}
-	}
 	# No Qt versions know about CONFIG(c++03), since
 	# its our own internal hint -- so for CONFIG(c++03)
-	# we set QMAKE_CXXFLAGS and QMAKE_LFLAGS for both Qt 4
-	# and Qt 5.
+	# we set QMAKE_CXXFLAGS and QMAKE_LFLAGS.
 	CONFIG(c++03):!CONFIG(c++11):!CONFIG(c++14):!CONFIG(c++1z) {
 		# Note: we use -std=c++98 to support
 		# older compilers. In GCC, the following
diff --git a/qmake/pkgconfig.pri b/qmake/pkgconfig.pri
index 44bd32f31..06011bc07 100644
--- a/qmake/pkgconfig.pri
+++ b/qmake/pkgconfig.pri
@@ -5,13 +5,7 @@
 
 # Allow cross-building by making a call to return the pkg-config
 # that the user supplied to the build.
-# pkgConfigExecutable() is part of Qt5.
-# If building with Qt4, pkg-config is called instead
-isEqual(QT_MAJOR_VERSION, 5) {
-	PKG_CONFIG = $$pkgConfigExecutable()
-} else {
-	PKG_CONFIG = "pkg-config"
-}
+PKG_CONFIG = $$pkgConfigExecutable()
 
 # must_pkgconfig(pkg)
 #
diff --git a/src/Connection.h b/src/Connection.h
index 534d2b8e8..9bc24ab05 100644
--- a/src/Connection.h
+++ b/src/Connection.h
@@ -14,15 +14,9 @@
 
 #include "CryptState.h"
 
-#include <QtCore/QMutex>
-
-#if QT_VERSION >= 0x040700
-# include <QtCore/QElapsedTimer>
-#else
-# include <QtCore/QTime>
-#endif
-
+#include <QtCore/QElapsedTimer>
 #include <QtCore/QList>
+#include <QtCore/QMutex>
 #include <QtCore/QObject>
 #include <QtNetwork/QSslSocket>
 
@@ -42,11 +36,7 @@ class Connection : public QObject {
 		Q_DISABLE_COPY(Connection)
 	protected:
 		QSslSocket *qtsSocket;
-#if QT_VERSION >= 0x040700
 		QElapsedTimer qtLastPacket;
-#else
-		QTime qtLastPacket;
-#endif
 		unsigned int uiType;
 		int iPacketLength;
 #ifdef Q_OS_WIN
@@ -100,8 +90,4 @@ class Connection : public QObject {
 #endif
 };
 
-#if QT_VERSION < 0x050000
-Q_DECLARE_METATYPE(QAbstractSocket::SocketError)
-#endif
-
 #endif
diff --git a/src/QAtomicIntCompat.h b/src/QAtomicIntCompat.h
deleted file mode 100644
index 7fb08d16e..000000000
--- a/src/QAtomicIntCompat.h
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2005-2019 The Mumble Developers. All rights reserved.
-// Use of this source code is governed by a BSD-style license
-// that can be found in the LICENSE file at the root of the
-// Mumble source tree or at <https://www.mumble.info/LICENSE>.
-
-#ifndef MUMBLE_QATOMICINTCOMPAT_H_
-#define MUMBLE_QATOMICINTCOMPAT_H_
-
-// Portably (between Qt 4 and Qt 5) load the value
-// of a QAtomicInt.
-inline int QAtomicIntLoad(const QAtomicInt &ai) {
-#if QT_VERSION >= 0x050000
-	return ai.load();
-#else
-	return int(ai);
-#endif
-}
-
-#endif
diff --git a/src/Qt4Compat.h b/src/Qt4Compat.h
deleted file mode 100644
index 32d185b33..000000000
--- a/src/Qt4Compat.h
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2005-2019 The Mumble Developers. All rights reserved.
-// Use of this source code is governed by a BSD-style license
-// that can be found in the LICENSE file at the root of the
-// Mumble source tree or at <https://www.mumble.info/LICENSE>.
-
-#ifndef MUMBLE_QT4COMPAT_H_
-#define MUMBLE_QT4COMPAT_H_
-
-namespace Qt {
-
-inline QString escape(const QString &plain) {
-	return plain.toHtmlEscaped();
-}
-
-}
-
-#endif
\ No newline at end of file
diff --git a/src/SSL.cpp b/src/SSL.cpp
index 6b803204b..c7d9ed145 100644
--- a/src/SSL.cpp
+++ b/src/SSL.cpp
@@ -108,120 +108,7 @@ out:
 }
 
 void MumbleSSL::addSystemCA() {
-#if QT_VERSION < 0x040700 && !defined(NO_SYSTEM_CA_OVERRIDE)
-#if defined(Q_OS_WIN)
-	QStringList qsl;
-	qsl << QLatin1String("Ca");
-	qsl << QLatin1String("Root");
-	qsl << QLatin1String("AuthRoot");
-	foreach(const QString &store, qsl) {
-		HCERTSTORE hCertStore;
-		PCCERT_CONTEXT pCertContext = NULL;
-
-		bool found = false;
-
-		hCertStore = CertOpenSystemStore(NULL, store.utf16());
-		if (! hCertStore) {
-			qWarning("SSL: Failed to open CA store %s", qPrintable(store));
-			continue;
-		}
-
-		while (pCertContext = CertEnumCertificatesInStore(hCertStore, pCertContext)) {
-			QByteArray qba(reinterpret_cast<const char *>(pCertContext->pbCertEncoded), pCertContext->cbCertEncoded);
-
-			QList<QSslCertificate> ql = QSslCertificate::fromData(qba, QSsl::Pem);
-			ql += QSslCertificate::fromData(qba, QSsl::Der);
-			if (! ql.isEmpty()) {
-				found = true;
-				QSslSocket::addDefaultCaCertificates(ql);
-			}
-		}
-		if (found)
-			qWarning("SSL: Added CA certificates from system store '%s'", qPrintable(store));
-
-		CertCloseStore(hCertStore, 0);
-	}
-
-#elif defined(Q_OS_MAC)
-	CFArrayRef certs = NULL;
-	bool found = false;
-
-	if (SecTrustCopyAnchorCertificates(&certs) == noErr) {
-		int ncerts = CFArrayGetCount(certs);
-		for (int i = 0; i < ncerts; i++) {
-			CFDataRef data = NULL;
-
-			SecCertificateRef cert = reinterpret_cast<SecCertificateRef>(const_cast<void *>(CFArrayGetValueAtIndex(certs, i)));
-			if (! cert)
-				continue;
-
-			if (SecKeychainItemExport(cert, kSecFormatX509Cert, kSecItemPemArmour, NULL, &data) == noErr) {
-				const char *ptr = reinterpret_cast<const char *>(CFDataGetBytePtr(data));
-				int len = CFDataGetLength(data);
-				QByteArray qba(ptr, len);
-
-				QList<QSslCertificate> ql = QSslCertificate::fromData(qba, QSsl::Pem);
-				if (! ql.isEmpty()) {
-					found = true;
-					QSslSocket::addDefaultCaCertificates(ql);
-				}
-			}
-		}
-
-		CFRelease(certs);
-
-		if (found)
-			qWarning("SSL: Added CA certificates from 'System Roots' store.");
-	}
-#elif defined(Q_OS_UNIX)
-	QStringList qsl;
-
-#ifdef SYSTEM_CA_DIR
-	QSslSocket::addDefaultCaCertificates(QLatin1String(MUMTEXT(SYSTEM_CA_DIR)));
-#else
-#ifdef SYSTEM_CA_BUNDLE
-	qsl << QLatin1String(MUMTEXT(SYSTEM_CA_BUNDLE));
-#else
-#ifdef __FreeBSD__
-	qsl << QLatin1String("/usr/local/share/certs/ca-root-nss.crt");
-#else
-	qsl << QLatin1String("/etc/pki/tls/certs/ca-bundle.crt");
-	qsl << QLatin1String("/etc/ssl/certs/ca-certificates.crt");
-#endif
-#endif
-
-	foreach(const QString &filename, qsl) {
-		QFile f(filename);
-		if (f.exists() && f.open(QIODevice::ReadOnly)) {
-			QList<QSslCertificate> ql = QSslCertificate::fromDevice(&f, QSsl::Pem);
-			ql += QSslCertificate::fromDevice(&f, QSsl::Der);
-			if (! ql.isEmpty()) {
-				qWarning("SSL: Added CA certificates from '%s'", qPrintable(filename));
-				QSslSocket::addDefaultCaCertificates(ql);
-			}
-		}
-	}
-#endif // SYSTEM_CA_DIR
-#endif // Q_OS_UNIX
-
-	QSet<QByteArray> digests;
-	QList<QSslCertificate> ql;
-	foreach(const QSslCertificate &crt, QSslSocket::defaultCaCertificates()) {
-		QByteArray digest = crt.digest(QCryptographicHash::Sha1);
-		if (! digests.contains(digest) && crt.isValid()) {
-			ql << crt;
-			digests.insert(digest);
-		}
-	}
-	QSslSocket::setDefaultCaCertificates(ql);
-#endif // NO_SYSTEM_CA_OVERRIDE
-
-	// Don't perform on-demand loading of root certificates
-#if QT_VERSION >= 0x050500
 	QSslSocket::addDefaultCaCertificates(QSslConfiguration::systemCaCertificates());
-#elif QT_VERSION >= 0x040800
-	QSslSocket::addDefaultCaCertificates(QSslSocket::systemCaCertificates());
-#endif
 
 #ifdef Q_OS_WIN
 	// Work around issue #1271.
@@ -233,7 +120,6 @@ void MumbleSSL::addSystemCA() {
 
 		QList<QSslCertificate> filteredCaList;
 		foreach (QSslCertificate cert, caList) {
-#if QT_VERSION >= 0x050000
 			QStringList orgs = cert.subjectInfo(QSslCertificate::Organization);
 			bool skip = false;
 			foreach (QString ou, orgs) {
@@ -245,12 +131,7 @@ void MumbleSSL::addSystemCA() {
 			if (skip) {
 				continue;
 			}
-#else
-			QString ou = cert.subjectInfo(QSslCertificate::Organization);
-			if (ou.contains(QLatin1String("Skype"), Qt::CaseInsensitive)) {
-				continue;
-			}
-#endif
+
 			filteredCaList.append(cert);
 		}
 
@@ -266,21 +147,15 @@ QString MumbleSSL::protocolToString(QSsl::SslProtocol protocol) {
 	switch(protocol) {
 		case QSsl::SslV3: return QLatin1String("SSL 3");
 		case QSsl::SslV2: return QLatin1String("SSL 2");
-#if QT_VERSION >= 0x050000
 		case QSsl::TlsV1_0: return QLatin1String("TLS 1.0");
 		case QSsl::TlsV1_1: return QLatin1String("TLS 1.1");
 		case QSsl::TlsV1_2: return QLatin1String("TLS 1.2");
 #if QT_VERSION >= 0x050C00
 		case QSsl::TlsV1_3: return QLatin1String("TLS 1.3");
-#endif
-#else
-		case QSsl::TlsV1: return  QLatin1String("TLS 1.0");
 #endif
 		case QSsl::AnyProtocol: return QLatin1String("AnyProtocol");
-#if QT_VERSION >= 0x040800
 		case QSsl::TlsV1SslV3: return QLatin1String("TlsV1SslV3");
 		case QSsl::SecureProtocols: return QLatin1String("SecureProtocols");
-#endif
 		default:
 		case QSsl::UnknownProtocol: return QLatin1String("UnknownProtocol");
 	}
diff --git a/src/ServerResolver_qt5.cpp b/src/ServerResolver.cpp
similarity index 99%
rename from src/ServerResolver_qt5.cpp
rename to src/ServerResolver.cpp
index 299ba6a07..55bbf7cf9 100644
--- a/src/ServerResolver_qt5.cpp
+++ b/src/ServerResolver.cpp
@@ -157,4 +157,4 @@ QList<ServerResolverRecord> ServerResolver::records() {
 	return QList<ServerResolverRecord>();
 }
 
-#include "ServerResolver_qt5.moc"
+#include "ServerResolver.moc"
diff --git a/src/ServerResolver_nosrv.cpp b/src/ServerResolver_nosrv.cpp
deleted file mode 100644
index 07b62bdfb..000000000
--- a/src/ServerResolver_nosrv.cpp
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright 2005-2019 The Mumble Developers. All rights reserved.
-// Use of this source code is governed by a BSD-style license
-// that can be found in the LICENSE file at the root of the
-// Mumble source tree or at <https://www.mumble.info/LICENSE>.
-
-#include "ServerResolver.h"
-
-#include <QtNetwork/QHostInfo>
-
-class ServerResolverPrivate : public QObject {
-	private:
-		Q_OBJECT
-		Q_DISABLE_COPY(ServerResolverPrivate)
-	public:
-		ServerResolverPrivate(QObject *parent);
-
-		void resolve(QString hostname, quint16 port);
-		QList<ServerResolverRecord> records();
-
-		QString m_origHostname;
-		quint16 m_origPort;
-
-		QList<ServerResolverRecord> m_resolved;
-
-	signals:
-		void resolved();
-
-	public slots:
-		void hostResolved(QHostInfo hostInfo);
-};
-
-ServerResolverPrivate::ServerResolverPrivate(QObject *parent)
-	: QObject(parent)
-	, m_origPort(0) {
-}
-
-void ServerResolverPrivate::resolve(QString hostname, quint16 port) {
-	m_origHostname = hostname;
-	m_origPort = port;
-
-	QHostInfo::lookupHost(hostname, this, SLOT(hostResolved(QHostInfo)));
-}
-
-QList<ServerResolverRecord> ServerResolverPrivate::records() {
-	return m_resolved;
-}
-
-void ServerResolverPrivate::hostResolved(QHostInfo hostInfo) {
-	if (hostInfo.error() == QHostInfo::NoError) {
-		QList<QHostAddress> resolvedAddresses = hostInfo.addresses();
-		
-		// Convert QHostAddress -> HostAddress.
-		QList<HostAddress> addresses;
-		foreach (QHostAddress ha, resolvedAddresses) {
-			addresses << HostAddress(ha);
-		}
-
-		m_resolved << ServerResolverRecord(m_origHostname, m_origPort, 0, addresses);
-	}
-
-	emit resolved();
-}
-
-ServerResolver::ServerResolver(QObject *parent)
-	: QObject(parent) {
-
-	d = new ServerResolverPrivate(this);
-}
-
-QString ServerResolver::hostname() {
-	if (d) {
-		return d->m_origHostname;
-	}
-
-	return QString();
-}
-
-quint16 ServerResolver::port() {
-	if (d) {
-		return d->m_origPort;
-	}
-
-	return 0;
-}
-
-void ServerResolver::resolve(QString hostname, quint16 port) {
-	if (d) {
-		connect(d, SIGNAL(resolved()), this, SIGNAL(resolved()));
-		d->resolve(hostname, port);
-	}
-}
-
-QList<ServerResolverRecord> ServerResolver::records() {
-	if (d) {
-		return d->records();
-	}
-	return QList<ServerResolverRecord>();
-}
-
-#include "ServerResolver_nosrv.moc"
diff --git a/src/Utils.h b/src/Utils.h
index a1a66e2f6..5de584299 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -8,9 +8,6 @@
 #ifndef MUMBLE_UTILS_H_
 #define MUMBLE_UTILS_H_
 
-#include "QAtomicIntCompat.h"
-#include "Qt4Compat.h"
-
 #include <QtCore/QtGlobal>
 
 #define iroundf(x) ( static_cast<int>(x) )
diff --git a/src/mumble.pri b/src/mumble.pri
index 878e590b9..630f7e12d 100644
--- a/src/mumble.pri
+++ b/src/mumble.pri
@@ -72,7 +72,7 @@ SOURCES *= \
   EnvUtils.cpp \
   UnresolvedServerAddress.cpp \
   ServerAddress.cpp \
-  ServerResolver_qt5.cpp \
+  ServerResolver.cpp \
   ServerResolverRecord.cpp \
   SelfSignedCertificate.cpp \
   SSLLocks.cpp \
@@ -80,16 +80,6 @@ SOURCES *= \
 
 LIBS		*= -lmumble_proto
 
-equals(QT_MAJOR_VERSION, 4) {
-	CONFIG *= no-srv
-}
-
-CONFIG(no-srv) {
-	DEFINES += USE_NO_SRV
-	SOURCES -= ServerResolver_qt5.cpp
-	SOURCES *= ServerResolver_nosrv.cpp
-}
-
 # Add arc4random_uniform
 INCLUDEPATH *= ../../3rdparty/arc4random-src
 SOURCES *= ../../3rdparty/arc4random-src/arc4random_uniform.cpp
@@ -130,13 +120,6 @@ unix {
 	QMAKE_CXXFLAGS *= "-I../mumble_proto" "-isystem ../mumble_proto"
 }
 
-# Make Q_DECL_OVERRIDE and Q_DECL_FINAL no-ops
-# for Qt 4.
-isEqual(QT_MAJOR_VERSION, 4) {
-	DEFINES *= Q_DECL_OVERRIDE=
-	DEFINES *= Q_DECL_FINAL=
-}
-
 CONFIG(debug, debug|release) {
   CONFIG += console
 }
diff --git a/src/mumble/ALSAAudio.cpp b/src/mumble/ALSAAudio.cpp
index 06b282f9e..9f5173017 100644
--- a/src/mumble/ALSAAudio.cpp
+++ b/src/mumble/ALSAAudio.cpp
@@ -338,7 +338,7 @@ void ALSAAudioInput::run() {
 			snd_pcm_close(capture_handle);
 			capture_handle = NULL;
 		}
-		g.mw->msgBox(tr("Opening chosen ALSA Input failed: %1").arg(Qt::escape(QLatin1String(snd_strerror(err)))));
+		g.mw->msgBox(tr("Opening chosen ALSA Input failed: %1").arg(QString::fromLatin1(snd_strerror(err)).toHtmlEscaped()));
 		return;
 	}
 
@@ -476,7 +476,7 @@ void ALSAAudioOutput::run() {
 			snd_pcm_writei(pcm_handle, zerobuff, period_size);
 
 	if (! bOk) {
-		g.mw->msgBox(tr("Opening chosen ALSA Output failed: %1").arg(Qt::escape(QLatin1String(snd_strerror(err)))));
+		g.mw->msgBox(tr("Opening chosen ALSA Output failed: %1").arg(QString::fromLatin1(snd_strerror(err)).toHtmlEscaped()));
 		if (pcm_handle) {
 			snd_pcm_close(pcm_handle);
 			pcm_handle = NULL;
diff --git a/src/mumble/ASIOInput.cpp b/src/mumble/ASIOInput.cpp
index e6fc34e9f..49cbd0aff 100644
--- a/src/mumble/ASIOInput.cpp
+++ b/src/mumble/ASIOInput.cpp
@@ -256,7 +256,7 @@ void ASIOConfig::on_qpbQuery_clicked() {
 			char err[255];
 			iasio->getErrorMessage(err);
 			SleepEx(10, false);
-			QMessageBox::critical(this, QLatin1String("Mumble"), tr("ASIO Initialization failed: %1").arg(Qt::escape(QLatin1String(err))), QMessageBox::Ok, QMessageBox::NoButton);
+			QMessageBox::critical(this, QLatin1String("Mumble"), tr("ASIO Initialization failed: %1").arg(QString::fromLatin1(err).toHtmlEscaped()), QMessageBox::Ok, QMessageBox::NoButton);
 		}
 		iasio->Release();
 	} else {
@@ -281,7 +281,7 @@ void ASIOConfig::on_qpbConfig_clicked() {
 			char err[255];
 			iasio->getErrorMessage(err);
 			SleepEx(10, false);
-			QMessageBox::critical(this, QLatin1String("Mumble"), tr("ASIO Initialization failed: %1").arg(Qt::escape(QLatin1String(err))), QMessageBox::Ok, QMessageBox::NoButton);
+			QMessageBox::critical(this, QLatin1String("Mumble"), tr("ASIO Initialization failed: %1").arg(QString::fromLatin1(err).toHtmlEscaped()), QMessageBox::Ok, QMessageBox::NoButton);
 		}
 		iasio->Release();
 	} else {
diff --git a/src/mumble/About.cpp b/src/mumble/About.cpp
index eef2f44e4..9885e9deb 100644
--- a/src/mumble/About.cpp
+++ b/src/mumble/About.cpp
@@ -36,9 +36,9 @@ AboutDialog::AboutDialog(QWidget *p) : QDialog(p) {
 	QList<LicenseInfo> thirdPartyLicenses = License::thirdPartyLicenses();
 	foreach(LicenseInfo li, thirdPartyLicenses) {
 		qtb3rdPartyLicense->append(QString::fromLatin1("<h3>%1 (<a href=\"%2\">%2</a>)</h3><pre>%3</pre>")
-				.arg(Qt::escape(li.name))
-				.arg(Qt::escape(li.url))
-				.arg(Qt::escape(li.license)));
+				.arg(li.name.toHtmlEscaped())
+				.arg(li.url.toHtmlEscaped())
+				.arg(li.license.toHtmlEscaped()));
 	}
 
 	qtb3rdPartyLicense->moveCursor(QTextCursor::Start);
diff --git a/src/mumble/About.h b/src/mumble/About.h
index 06476b266..73cda9c18 100644
--- a/src/mumble/About.h
+++ b/src/mumble/About.h
@@ -8,11 +8,7 @@
 
 #include <QtCore/QtGlobal>
 #include <QtCore/QObject>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QDialog>
-#else
-# include <QtGui/QDialog>
-#endif
+#include <QtWidgets/QDialog>
 
 class AboutDialog : public QDialog {
 	private:
diff --git a/src/mumble/AudioConfigDialog.cpp b/src/mumble/AudioConfigDialog.cpp
index 96405be4a..e19a5c36f 100644
--- a/src/mumble/AudioConfigDialog.cpp
+++ b/src/mumble/AudioConfigDialog.cpp
@@ -371,7 +371,7 @@ void AudioInputDialog::on_qcbSystem_currentIndexChanged(int) {
 
 		foreach(audioDevice d, ql) {
 			qcbDevice->addItem(d.first, d.second);
-			qcbDevice->setItemData(idx, Qt::escape(d.first), Qt::ToolTipRole);
+			qcbDevice->setItemData(idx, d.first.toHtmlEscaped(), Qt::ToolTipRole);
 			++idx;
 		}
 
@@ -524,7 +524,7 @@ void AudioOutputDialog::on_qcbSystem_currentIndexChanged(int) {
 
 		foreach(audioDevice d, ql) {
 			qcbDevice->addItem(d.first, d.second);
-			qcbDevice->setItemData(idx, Qt::escape(d.first), Qt::ToolTipRole);
+			qcbDevice->setItemData(idx, d.first.toHtmlEscaped(), Qt::ToolTipRole);
 			++idx;
 		}
 		bool canmute = aor->canMuteOthers();
diff --git a/src/mumble/AudioOutputSample.cpp b/src/mumble/AudioOutputSample.cpp
index 099e4b0f0..a6217eba7 100644
--- a/src/mumble/AudioOutputSample.cpp
+++ b/src/mumble/AudioOutputSample.cpp
@@ -194,7 +194,7 @@ QString AudioOutputSample::browseForSndfile(QString defaultpath) {
 		if (sf == NULL) {
 			QMessageBox::critical(NULL,
 			                      tr("Invalid sound file"),
-			                      tr("The file '%1' cannot be used by Mumble. Please select a file with a compatible format and encoding.").arg(Qt::escape(file)));
+			                      tr("The file '%1' cannot be used by Mumble. Please select a file with a compatible format and encoding.").arg(file.toHtmlEscaped()));
 			return QString();
 		}
 		delete sf;
diff --git a/src/mumble/AudioStats.h b/src/mumble/AudioStats.h
index 46e91be79..e67f9bc73 100644
--- a/src/mumble/AudioStats.h
+++ b/src/mumble/AudioStats.h
@@ -9,11 +9,7 @@
 #include <QtCore/QtGlobal>
 #include <QtCore/QList>
 #include <QtCore/QTimer>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QWidget>
-#else
-# include <QtGui/QWidget>
-#endif
+#include <QtWidgets/QWidget>
 
 class AudioBar : public QWidget {
 	private:
diff --git a/src/mumble/AudioWizard.h b/src/mumble/AudioWizard.h
index ddd500fce..12b76bd85 100644
--- a/src/mumble/AudioWizard.h
+++ b/src/mumble/AudioWizard.h
@@ -7,13 +7,8 @@
 #define MUMBLE_MUMBLE_AUDIOWIZARD_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QWizard>
-# include <QtWidgets/QWizardPage>
-#else
-# include <QtGui/QWizard>
-# include <QtGui/QWizardPage>
-#endif
+#include <QtWidgets/QWizard>
+#include <QtWidgets/QWizardPage>
 
 #include "AudioStats.h"
 #include "AudioOutput.h"
diff --git a/src/mumble/Cert.cpp b/src/mumble/Cert.cpp
index fabcfb956..f07dcda47 100644
--- a/src/mumble/Cert.cpp
+++ b/src/mumble/Cert.cpp
@@ -79,7 +79,6 @@ void CertView::setCert(const QList<QSslCertificate> &cert) {
 	} else {
 		QSslCertificate qscCert = qlCert.at(0);
 
-#if QT_VERSION >= 0x050000
 		const QStringList &names = qscCert.subjectInfo(QSslCertificate::CommonName);
 		QString name;
 		if (names.count() > 0) {
@@ -87,10 +86,6 @@ void CertView::setCert(const QList<QSslCertificate> &cert) {
 		}
 
 		QStringList emails = qscCert.subjectAlternativeNames().values(QSsl::EmailEntry);
-#else
-		const QString &name = qscCert.subjectInfo(QSslCertificate::CommonName);
-		QStringList emails(qscCert.alternateSubjectNames().values(QSsl::EmailEntry));
-#endif
 
 		QString tmpName = name;
 		tmpName = tmpName.replace(QLatin1String("\\x"), QLatin1String("%"));
@@ -104,22 +99,19 @@ void CertView::setCert(const QList<QSslCertificate> &cert) {
 			qlSubjectEmail->setText(tr("(none)"));
 
 		if (qscCert.expiryDate() <= QDateTime::currentDateTime())
-			qlExpiry->setText(QString::fromLatin1("<font color=\"red\"><b>%1</b></font>").arg(Qt::escape(qscCert.expiryDate().toString(Qt::SystemLocaleDate))));
+			qlExpiry->setText(QString::fromLatin1("<font color=\"red\"><b>%1</b></font>").arg(qscCert.expiryDate().toString(Qt::SystemLocaleDate).toHtmlEscaped()));
 		else
 			qlExpiry->setText(qscCert.expiryDate().toString(Qt::SystemLocaleDate));
 
 		if (qlCert.count() > 1)
 			qscCert = qlCert.last();
 
-#if QT_VERSION >= 0x050000
 		const QStringList &issuerNames = qscCert.issuerInfo(QSslCertificate::CommonName);
 		QString issuerName;
 		if (issuerNames.count() > 0) {
 			issuerName = issuerNames.at(0);
 		}
-#else
-		const QString &issuerName = qscCert.issuerInfo(QSslCertificate::CommonName);
-#endif
+
 		qlIssuerName->setText((issuerName == name) ? tr("Self-signed") : issuerName);
 	}
 }
diff --git a/src/mumble/Cert.h b/src/mumble/Cert.h
index 729b0f5e5..a62ca44ab 100644
--- a/src/mumble/Cert.h
+++ b/src/mumble/Cert.h
@@ -8,11 +8,7 @@
 
 #include <QtCore/QtGlobal>
 #include <QtCore/QString>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QGroupBox>
-#else
-# include <QtGui/QGroupBox>
-#endif
+#include <QtWidgets/QGroupBox>
 
 #include <QtNetwork/QHostInfo>
 #include <QtNetwork/QSslCertificate>
diff --git a/src/mumble/ConfigWidget.h b/src/mumble/ConfigWidget.h
index d5379b0f7..34c4f95a1 100644
--- a/src/mumble/ConfigWidget.h
+++ b/src/mumble/ConfigWidget.h
@@ -8,11 +8,7 @@
 
 #include <QtCore/QtGlobal>
 #include <QtCore/QObject>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QWidget> 
-#else 
-# include <QtGui/QWidget>
-#endif
+#include <QtWidgets/QWidget>
 
 struct Settings;
 class ConfigDialog;
diff --git a/src/mumble/ConnectDialog.cpp b/src/mumble/ConnectDialog.cpp
index aa622162d..56adf2c75 100644
--- a/src/mumble/ConnectDialog.cpp
+++ b/src/mumble/ConnectDialog.cpp
@@ -415,16 +415,10 @@ ServerItem *ServerItem::fromMimeData(const QMimeData *mime, bool default_name, Q
 	}
 
 	if (default_name) {
-#if QT_VERSION >= 0x050000
 		QUrlQuery query(url);
 		if (! query.hasQueryItem(QLatin1String("title"))) {
 			query.addQueryItem(QLatin1String("title"), url.host());
 		}
-#else
-		if (! url.hasQueryItem(QLatin1String("title"))) {
-			url.addQueryItem(QLatin1String("title"), url.host());
-		}
-#endif
 	}
 
 	if (! url.isValid()) {
@@ -454,9 +448,7 @@ ServerItem *ServerItem::fromUrl(QUrl url, QWidget *p) {
 		return NULL;
 	}
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query(url);
-#endif
 
 	if (url.userName().isEmpty()) {
 		if (g.s.qsUsername.isEmpty()) {
@@ -471,17 +463,10 @@ ServerItem *ServerItem::fromUrl(QUrl url, QWidget *p) {
 		url.setUserName(g.s.qsUsername);
 	}
 
-#if QT_VERSION >= 0x050000
 	ServerItem *si = new ServerItem(query.queryItemValue(QLatin1String("title")), url.host(), static_cast<unsigned short>(url.port(DEFAULT_MUMBLE_PORT)), url.userName(), url.password());
 
 	if (query.hasQueryItem(QLatin1String("url")))
 		si->qsUrl = query.queryItemValue(QLatin1String("url"));
-#else
-	ServerItem *si = new ServerItem(url.queryItemValue(QLatin1String("title")), url.host(), static_cast<unsigned short>(url.port(DEFAULT_MUMBLE_PORT)), url.userName(), url.password());
-
-	if (url.hasQueryItem(QLatin1String("url")))
-		si->qsUrl = url.queryItemValue(QLatin1String("url"));
-#endif
 
 	return si;
 }
@@ -521,7 +506,8 @@ QVariant ServerItem::data(int column, int role) const {
 		} else if (role == Qt::ToolTipRole) {
 			QStringList qsl;
 			foreach(const ServerAddress &addr, qlAddresses) {
-				qsl << Qt::escape(addr.host.toString() + QLatin1String(":") + QString::number(static_cast<unsigned long>(addr.port)));
+				const QString qsAddress = addr.host.toString() + QLatin1String(":") + QString::number(static_cast<unsigned long>(addr.port));
+				qsl << qsAddress.toHtmlEscaped();
 			}
 
 			double ploss = 100.0;
@@ -532,18 +518,18 @@ QVariant ServerItem::data(int column, int role) const {
 			QString qs;
 			qs +=
 			    QLatin1String("<table>") +
-			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Servername"), Qt::escape(qsName)) +
-			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Hostname"), Qt::escape(qsHostname));
+			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Servername"), qsName.toHtmlEscaped()) +
+			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Hostname"), qsHostname.toHtmlEscaped());
 
 			if (! qsBonjourHost.isEmpty())
-				qs += QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Bonjour name"), Qt::escape(qsBonjourHost));
+				qs += QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Bonjour name"), qsBonjourHost.toHtmlEscaped());
 
 			qs +=
 			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Port")).arg(usPort) +
 			    QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Addresses"), qsl.join(QLatin1String(", ")));
 
 			if (! qsUrl.isEmpty())
-				qs += QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Website"), Qt::escape(qsUrl));
+				qs += QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Website"), qsUrl.toHtmlEscaped());
 
 			if (uiSent > 0) {
 				qs += QString::fromLatin1("<tr><th align=left>%1</th><td>%2</td></tr>").arg(ConnectDialog::tr("Packet loss"), QString::fromLatin1("%1% (%2/%3)").arg(ploss, 0, 'f', 1).arg(uiRecv).arg(uiSent));
@@ -671,15 +657,10 @@ QMimeData *ServerItem::toMimeData(const QString &name, const QString &host, unsi
 		url.setPort(port);
 	url.setPath(channel);
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query;
 	query.addQueryItem(QLatin1String("title"), name);
 	query.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
 	url.setQuery(query);
-#else
-	url.addQueryItem(QLatin1String("title"), name);
-	url.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
-#endif
 
 	QString qs = QLatin1String(url.toEncoded());
 
@@ -723,7 +704,7 @@ QMimeData *ServerItem::toMimeData(const QString &name, const QString &host, unsi
 	mime->setUrls(urls);
 
 	mime->setText(qs);
-	mime->setHtml(QString::fromLatin1("<a href=\"%1\">%2</a>").arg(qs).arg(Qt::escape(name)));
+	mime->setHtml(QString::fromLatin1("<a href=\"%1\">%2</a>").arg(qs).arg(name.toHtmlEscaped()));
 
 	return mime;
 }
@@ -1011,7 +992,6 @@ ConnectDialog::ConnectDialog(QWidget *p, bool autoconnect) : QDialog(p), bAutoCo
 
 	qtwServers->sortItems(1, Qt::AscendingOrder);
 
-#if QT_VERSION >= 0x050000
 	qtwServers->header()->setSectionResizeMode(0, QHeaderView::Stretch);
 	if (qtwServers->columnCount() >= 2) {
 		qtwServers->header()->setSectionResizeMode(1, QHeaderView::ResizeToContents);
@@ -1019,15 +999,6 @@ ConnectDialog::ConnectDialog(QWidget *p, bool autoconnect) : QDialog(p), bAutoCo
 	if (qtwServers->columnCount() >= 3) {
 		qtwServers->header()->setSectionResizeMode(2, QHeaderView::ResizeToContents);
 	}
-#else
-	qtwServers->header()->setResizeMode(0, QHeaderView::Stretch);
-	if (qtwServers->columnCount() >= 2) {
-		qtwServers->header()->setResizeMode(1, QHeaderView::ResizeToContents);
-	}
-	if (qtwServers->columnCount() >= 3) {
-		qtwServers->header()->setResizeMode(2, QHeaderView::ResizeToContents);
-	}
-#endif
 
 	connect(qtwServers->header(), SIGNAL(sortIndicatorChanged(int, Qt::SortOrder)), this, SLOT(OnSortChanged(int, Qt::SortOrder)));
 
@@ -1379,13 +1350,10 @@ void ConnectDialog::initList() {
 
 	QUrl url;
 	url.setPath(QLatin1String("/v1/list"));
-#if QT_VERSION >= 0x050000
+
 	QUrlQuery query;
 	query.addQueryItem(QLatin1String("version"), QLatin1String(MUMTEXT(MUMBLE_VERSION_STRING)));
 	url.setQuery(query);
-#else
-	url.addQueryItem(QLatin1String("version"), QLatin1String(MUMTEXT(MUMBLE_VERSION_STRING)));
-#endif
 
 	WebFetch::fetch(QLatin1String("publist"), url, this, SLOT(fetched(QByteArray,QUrl,QMap<QString,QString>)));
 }
diff --git a/src/mumble/ConnectDialog.h b/src/mumble/ConnectDialog.h
index b2194f957..0463a40c6 100644
--- a/src/mumble/ConnectDialog.h
+++ b/src/mumble/ConnectDialog.h
@@ -14,15 +14,9 @@
 #include <QtCore/QtGlobal>
 #include <QtCore/QString>
 #include <QtCore/QUrl>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QStyledItemDelegate>
-# include <QtWidgets/QTreeView>
-# include <QtWidgets/QTreeWidgetItem>
-#else
-# include <QtGui/QStyledItemDelegate>
-# include <QtGui/QTreeView>
-# include <QtGui/QTreeWidgetItem>
-#endif
+#include <QtWidgets/QStyledItemDelegate>
+#include <QtWidgets/QTreeView>
+#include <QtWidgets/QTreeWidgetItem>
 
 #include <QtNetwork/QHostInfo>
 
diff --git a/src/mumble/CrashReporter.h b/src/mumble/CrashReporter.h
index c64ee83e2..45e6baa7a 100644
--- a/src/mumble/CrashReporter.h
+++ b/src/mumble/CrashReporter.h
@@ -9,18 +9,10 @@
 #include <QtCore/QObject>
 #include <QtCore/QEventLoop>
 #include <QtNetwork/QNetworkReply>
-
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QDialog>
-# include <QtWidgets/QProgressDialog>
-# include <QtWidgets/QLineEdit>
-# include <QtWidgets/QTextEdit>
-#else
-# include <QtGui/QDialog>
-# include <QtGui/QProgressDialog>
-# include <QtGui/QLineEdit>
-# include <QtGui/QTextEdit>
-#endif
+#include <QtWidgets/QDialog>
+#include <QtWidgets/QProgressDialog>
+#include <QtWidgets/QLineEdit>
+#include <QtWidgets/QTextEdit>
 
 class CrashReporter : QDialog {
 		Q_OBJECT
diff --git a/src/mumble/CustomElements.h b/src/mumble/CustomElements.h
index 985ec929a..59067201f 100644
--- a/src/mumble/CustomElements.h
+++ b/src/mumble/CustomElements.h
@@ -7,16 +7,9 @@
 #define MUMBLE_MUMBLE_CUSTOMELEMENTS_H_
 
 #include <QtCore/QObject>
-
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QLabel>
-# include <QtWidgets/QTextBrowser>
-# include <QtWidgets/QTextEdit>
-#else
-# include <QtGui/QLabel>
-# include <QtGui/QTextBrowser>
-# include <QtGui/QTextEdit>
-#endif
+#include <QtWidgets/QLabel>
+#include <QtWidgets/QTextBrowser>
+#include <QtWidgets/QTextEdit>
 
 class LogTextBrowser : public QTextBrowser {
 	private:
diff --git a/src/mumble/DBus.cpp b/src/mumble/DBus.cpp
index 646be653d..108797e71 100644
--- a/src/mumble/DBus.cpp
+++ b/src/mumble/DBus.cpp
@@ -46,13 +46,9 @@ void MumbleDBus::getCurrentUrl(const QDBusMessage &msg) {
 	u.setPort(port);
 	u.setUserName(user);
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query;
 	query.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
 	u.setQuery(query);
-#else
-	u.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
-#endif
 
 	QStringList path;
 	Channel *c = ClientUser::get(g.uiSession)->cChannel;
diff --git a/src/mumble/Database.cpp b/src/mumble/Database.cpp
index 941bb8080..da2ef6f34 100644
--- a/src/mumble/Database.cpp
+++ b/src/mumble/Database.cpp
@@ -47,11 +47,7 @@ Database::Database(const QString &dbname) {
 	int i;
 
 	datapaths << g.qdBasePath.absolutePath();
-#if QT_VERSION >= 0x050000
 	datapaths << QStandardPaths::writableLocation(QStandardPaths::DataLocation);
-#else
-	datapaths << QDesktopServices::storageLocation(QDesktopServices::DataLocation);
-#endif
 #if defined(Q_OS_UNIX) && ! defined(Q_OS_MAC)
 	datapaths << QDir::homePath() + QLatin1String("/.config/Mumble");
 #endif
@@ -100,7 +96,7 @@ Database::Database(const QString &dbname) {
 	QFileInfo fi(db.databaseName());
 
 	if (! fi.isWritable()) {
-		QMessageBox::critical(NULL, QLatin1String("Mumble"), tr("The database '%1' is read-only. Mumble cannot store server settings (i.e. SSL certificates) until you fix this problem.").arg(Qt::escape(fi.filePath())), QMessageBox::Ok | QMessageBox::Default, QMessageBox::NoButton);
+		QMessageBox::critical(NULL, QLatin1String("Mumble"), tr("The database '%1' is read-only. Mumble cannot store server settings (i.e. SSL certificates) until you fix this problem.").arg(fi.filePath().toHtmlEscaped()), QMessageBox::Ok | QMessageBox::Default, QMessageBox::NoButton);
 		qWarning("Database: Database is read-only");
 	}
 
diff --git a/src/mumble/DeveloperConsole.h b/src/mumble/DeveloperConsole.h
index 9c1573165..2f72fef98 100644
--- a/src/mumble/DeveloperConsole.h
+++ b/src/mumble/DeveloperConsole.h
@@ -8,12 +8,8 @@
 
 #include <QtCore/QStringList>
 #include <QtCore/QObject>
-# include <QtCore/QPointer>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QMainWindow>
-#else
-# include <QtGui/QMainWindow>
-#endif
+#include <QtCore/QPointer>
+#include <QtWidgets/QMainWindow>
 
 class DeveloperConsole : public QObject {
 	private:
diff --git a/src/mumble/Global.cpp b/src/mumble/Global.cpp
index 41ec60e17..f3b82aa85 100644
--- a/src/mumble/Global.cpp
+++ b/src/mumble/Global.cpp
@@ -20,11 +20,7 @@ Global *Global::g_global_struct;
 static void migrateDataDir() {
 #ifdef Q_OS_MAC
 	QString olddir = QDir::homePath() + QLatin1String("/Library/Preferences/Mumble");
-#if QT_VERSION >= 0x050000
 	QString newdir = QStandardPaths::writableLocation(QStandardPaths::DataLocation);
-#else
-	QString newdir = QDesktopServices::storageLocation(QDesktopServices::DataLocation);
-#endif // QT_VERSION
 	QString linksTo = QFile::symLinkTarget(olddir);
 	if (!QFile::exists(newdir) && QFile::exists(olddir) && linksTo.isEmpty()) {
 		QDir d;
@@ -49,7 +45,6 @@ static void migrateDataDir() {
 // Qt4 used another data directory on Unix-like systems, to ensure a seamless
 // transition we must first move the users data to the new directory.
 #if defined(Q_OS_UNIX) && ! defined(Q_OS_MAC)
-#if QT_VERSION >= 0x050000
 	QString olddir = QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + QLatin1String("/data/Mumble");
 	QString newdir = QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) + QLatin1String("/Mumble");
 
@@ -66,7 +61,6 @@ static void migrateDataDir() {
 	}
 
 	qWarning("Application data migration failed.");
-#endif // QT_VERSION
 #endif // defined(Q_OS_UNIX) && ! defined(Q_OS_MAC)
 }
 #endif // Q_OS_WIN
@@ -121,11 +115,8 @@ Global::Global() {
 
 	QStringList qsl;
 	qsl << QCoreApplication::instance()->applicationDirPath();
-#if QT_VERSION >= 0x050000
 	qsl << QStandardPaths::writableLocation(QStandardPaths::DataLocation);
-#else
-	qsl << QDesktopServices::storageLocation(QDesktopServices::DataLocation);
-#endif
+
 #if defined(Q_OS_WIN)
 	QString appdata;
 	wchar_t appData[MAX_PATH];
@@ -155,11 +146,7 @@ Global::Global() {
 			qdBasePath.setPath(appdata);
 #else
 		migrateDataDir();
-#if QT_VERSION >= 0x050000
 		qdBasePath.setPath(QStandardPaths::writableLocation(QStandardPaths::DataLocation));
-#else
-		qdBasePath.setPath(QDesktopServices::storageLocation(QDesktopServices::DataLocation));
-#endif
 #endif
 		if (! qdBasePath.exists()) {
 			QDir::root().mkpath(qdBasePath.absolutePath());
diff --git a/src/mumble/GlobalShortcut.cpp b/src/mumble/GlobalShortcut.cpp
index 26c5b5e19..6272285da 100644
--- a/src/mumble/GlobalShortcut.cpp
+++ b/src/mumble/GlobalShortcut.cpp
@@ -529,20 +529,11 @@ GlobalShortcutConfig::GlobalShortcutConfig(Settings &st) : ConfigWidget(st) {
 	qtwShortcuts->setColumnCount(canSuppress ? 4 : 3);
 	qtwShortcuts->setItemDelegate(new ShortcutDelegate(qtwShortcuts));
 
-#if QT_VERSION >= 0x050000
 	qtwShortcuts->header()->setSectionResizeMode(0, QHeaderView::Fixed);
 	qtwShortcuts->header()->resizeSection(0, 150);
 	qtwShortcuts->header()->setSectionResizeMode(2, QHeaderView::Stretch);
 	if (canSuppress)
 		qtwShortcuts->header()->setSectionResizeMode(3, QHeaderView::ResizeToContents);
-#else
-	qtwShortcuts->header()->setResizeMode(0, QHeaderView::Fixed);
-	qtwShortcuts->header()->resizeSection(0, 150);
-	qtwShortcuts->header()->setResizeMode(2, QHeaderView::Stretch);
-	if (canSuppress)
-		qtwShortcuts->header()->setResizeMode(3, QHeaderView::ResizeToContents);
-#endif
-
 
 	qcbEnableGlobalShortcuts->setVisible(canDisable);
 
diff --git a/src/mumble/GlobalShortcut.h b/src/mumble/GlobalShortcut.h
index 7ed07efaa..e1d1edbb1 100644
--- a/src/mumble/GlobalShortcut.h
+++ b/src/mumble/GlobalShortcut.h
@@ -8,13 +8,8 @@
 
 #include <QtCore/QtGlobal>
 #include <QtCore/QThread>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QToolButton>
-# include <QtWidgets/QStyledItemDelegate>
-#else
-# include <QtGui/QToolButton>
-# include <QtGui/QStyledItemDelegate>
-#endif
+#include <QtWidgets/QToolButton>
+#include <QtWidgets/QStyledItemDelegate>
 
 #include "ConfigDialog.h"
 #include "Timer.h"
diff --git a/src/mumble/LCD.cpp b/src/mumble/LCD.cpp
index 62385eaf9..8a909c4c4 100644
--- a/src/mumble/LCD.cpp
+++ b/src/mumble/LCD.cpp
@@ -88,7 +88,7 @@ LCDConfig::LCDConfig(Settings &st) : ConfigWidget(st) {
 		qtwi->setFlags(Qt::ItemIsEnabled |Qt::ItemIsUserCheckable);
 
 		qtwi->setText(0, d->name());
-		qtwi->setToolTip(0, Qt::escape(d->name()));
+		qtwi->setToolTip(0, d->name().toHtmlEscaped());
 
 		QSize lcdsize = d->size();
 		QString qsSize = QString::fromLatin1("%1x%2").arg(lcdsize.width()).arg(lcdsize.height());
diff --git a/src/mumble/Log.cpp b/src/mumble/Log.cpp
index 274da974d..3e39be694 100644
--- a/src/mumble/Log.cpp
+++ b/src/mumble/Log.cpp
@@ -39,21 +39,12 @@ LogConfig::LogConfig(Settings &st) : ConfigWidget(st) {
 	qgbTTS->setDisabled(true);
 #endif
 
-#if QT_VERSION >= 0x050000
 	qtwMessages->header()->setSectionResizeMode(ColMessage, QHeaderView::Stretch);
 	qtwMessages->header()->setSectionResizeMode(ColConsole, QHeaderView::ResizeToContents);
 	qtwMessages->header()->setSectionResizeMode(ColNotification, QHeaderView::ResizeToContents);
 	qtwMessages->header()->setSectionResizeMode(ColHighlight, QHeaderView::ResizeToContents);
 	qtwMessages->header()->setSectionResizeMode(ColTTS, QHeaderView::ResizeToContents);
 	qtwMessages->header()->setSectionResizeMode(ColStaticSound, QHeaderView::ResizeToContents);
-#else
-	qtwMessages->header()->setResizeMode(ColMessage, QHeaderView::Stretch);
-	qtwMessages->header()->setResizeMode(ColConsole, QHeaderView::ResizeToContents);
-	qtwMessages->header()->setResizeMode(ColNotification, QHeaderView::ResizeToContents);
-	qtwMessages->header()->setResizeMode(ColHighlight, QHeaderView::ResizeToContents);
-	qtwMessages->header()->setResizeMode(ColTTS, QHeaderView::ResizeToContents);
-	qtwMessages->header()->setResizeMode(ColStaticSound, QHeaderView::ResizeToContents);
-#endif
 
 	QTreeWidgetItem *twi;
 	for (int i = Log::firstMsgType; i <= Log::lastMsgType; ++i) {
@@ -301,7 +292,7 @@ QString Log::msgColor(const QString &text, LogColorType t) {
 }
 
 QString Log::formatChannel(::Channel *c) {
-	return QString::fromLatin1("<a href='channelid://%1/%3' class='log-channel'>%2</a>").arg(c->iId).arg(Qt::escape(c->qsName)).arg(QString::fromLatin1(g.sh->qbaDigest.toBase64()));
+	return QString::fromLatin1("<a href='channelid://%1/%3' class='log-channel'>%2</a>").arg(c->iId).arg(c->qsName.toHtmlEscaped()).arg(QString::fromLatin1(g.sh->qbaDigest.toBase64()));
 }
 
 QString Log::formatClientUser(ClientUser *cu, LogColorType t, const QString &displayName) {
@@ -313,7 +304,7 @@ QString Log::formatClientUser(ClientUser *cu, LogColorType t, const QString &dis
 	}
 
 	if (cu) {
-		QString name = Qt::escape(displayName.isNull() ? cu->qsName : displayName);
+		QString name = (displayName.isNull() ? cu->qsName : displayName).toHtmlEscaped();
 		if (cu->qsHash.isEmpty()) {
 			return QString::fromLatin1("<a href='clientid://%2/%4' class='log-user log-%1'>%3</a>").arg(className).arg(cu->uiSession).arg(name).arg(QString::fromLatin1(g.sh->qbaDigest.toBase64()));
 		} else {
@@ -489,7 +480,7 @@ void Log::log(MsgType mt, const QString &console, const QString &terse, bool own
 		if (qdDate != dt.date()) {
 			qdDate = dt.date();
 			tc.insertBlock();
-			tc.insertHtml(tr("[Date changed to %1]\n").arg(Qt::escape(qdDate.toString(Qt::DefaultLocaleShortDate))));
+			tc.insertHtml(tr("[Date changed to %1]\n").arg(qdDate.toString(Qt::DefaultLocaleShortDate).toHtmlEscaped()));
 			tc.movePosition(QTextCursor::End);
 		}
 
@@ -502,7 +493,7 @@ void Log::log(MsgType mt, const QString &console, const QString &terse, bool own
 		} else if (! g.mw->qteLog->document()->isEmpty()) {
 			tc.insertBlock();
 		}
-		tc.insertHtml(Log::msgColor(QString::fromLatin1("[%1] ").arg(Qt::escape(dt.time().toString())), Log::Time));
+		tc.insertHtml(Log::msgColor(QString::fromLatin1("[%1] ").arg(dt.time().toString().toHtmlEscaped()), Log::Time));
 		validHtml(console, &tc);
 		tc.movePosition(QTextCursor::End);
 		g.mw->qteLog->setTextCursor(tc);
diff --git a/src/mumble/MainWindow.cpp b/src/mumble/MainWindow.cpp
index 83911c152..5459778d7 100644
--- a/src/mumble/MainWindow.cpp
+++ b/src/mumble/MainWindow.cpp
@@ -135,11 +135,6 @@ MainWindow::MainWindow(QWidget *p) : QMainWindow(p) {
 
 	qwPTTButtonWidget = NULL;
 
-#if QT_VERSION < 0x050000
-	cuContextUser = QWeakPointer<ClientUser>();
-	cContextChannel = QWeakPointer<Channel>();
-#endif
-
 	qtReconnect = new QTimer(this);
 	qtReconnect->setInterval(10000);
 	qtReconnect->setSingleShot(true);
@@ -356,9 +351,7 @@ void MainWindow::setupGui()  {
 
 	updateTransmitModeComboBox();
 
-// For Qt >= 5, enable this call (only) for Windows.
-// For Qt < 5, enable for anything but macOS.
-#if (QT_VERSION >= 0x050000 && defined(Q_OS_WIN)) || (QT_VERSION < 0x050000 && !defined(Q_OS_MAC))
+#ifdef Q_OS_WIN
 	setupView(false);
 #endif
 
@@ -383,12 +376,6 @@ void MainWindow::setupGui()  {
 
 #ifdef Q_OS_MAC
 	setWindowOpacity(1.0f);
-#if QT_VERSION < 0x040700
-	// Process pending events.  This is done to force the unified
-	// toolbar to show up as soon as possible (and not wait until
-	// we are back into the Cocoa mainloop)
-	qApp->processEvents();
-#endif
 #endif
 }
 
@@ -437,12 +424,8 @@ void MainWindow::msgBox(QString msg) {
 }
 
 #ifdef Q_OS_WIN
-#if QT_VERSION >= 0x050000
 bool MainWindow::nativeEvent(const QByteArray &, void *message, long *) {
 	MSG *msg = reinterpret_cast<MSG *>(message);
-#else
-bool MainWindow::winEvent(MSG *msg, long *) {
-#endif
 	if (msg->message == WM_DEVICECHANGE && msg->wParam == DBT_DEVNODES_CHANGED)
 		uiNewHardware++;
 
@@ -795,17 +778,13 @@ void MainWindow::saveImageAs() {
 	updateImagePath(fname);
 
 	if (!ok) {
-		g.l->log(Log::Warning, tr("Could not save image: %1").arg(Qt::escape(fname)));
+		g.l->log(Log::Warning, tr("Could not save image: %1").arg(fname.toHtmlEscaped()));
 	}
 }
 
 QString MainWindow::getImagePath(QString filename) const {
 	if (g.s.qsImagePath.isEmpty() || ! QDir(g.s.qsImagePath).exists()) {
-#if QT_VERSION >= 0x050000
 		g.s.qsImagePath = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation);
-#else
-		g.s.qsImagePath = QDesktopServices::storageLocation(QDesktopServices::PicturesLocation);
-#endif
 	}
 	if (filename.isEmpty()) {
 		return g.s.qsImagePath;
@@ -841,7 +820,7 @@ static void recreateServerHandler() {
 }
 
 void MainWindow::openUrl(const QUrl &url) {
-	g.l->log(Log::Information, tr("Opening URL %1").arg(Qt::escape(url.toString())));
+	g.l->log(Log::Information, tr("Opening URL %1").arg(url.toString().toHtmlEscaped()));
 	if (url.scheme() == QLatin1String("file")) {
 		QFile f(url.toLocalFile());
 		if (! f.exists() || ! f.open(QIODevice::ReadOnly)) {
@@ -878,12 +857,8 @@ void MainWindow::openUrl(const QUrl &url) {
 	minor = 2;
 	patch = 0;
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query(url);
 	QString version = query.queryItemValue(QLatin1String("version"));
-#else
-	QString version = url.queryItemValue(QLatin1String("version"));
-#endif
 	MumbleVersion::get(&major, &minor, &patch, version);
 
 	if ((major < 1) || // No pre 1.2.0
@@ -902,13 +877,8 @@ void MainWindow::openUrl(const QUrl &url) {
 	qsDesiredChannel = url.path();
 	QString name;
 
-#if QT_VERSION >= 0x050000
 	if (query.hasQueryItem(QLatin1String("title")))
 		name = query.queryItemValue(QLatin1String("title"));
-#else
-	if (url.hasQueryItem(QLatin1String("title")))
-		name = url.queryItemValue(QLatin1String("title"));
-#endif
 
 	if (g.sh && g.sh->isRunning()) {
 		QString oHost, oUser, oPw;
@@ -942,7 +912,7 @@ void MainWindow::openUrl(const QUrl &url) {
 	rtLast = MumbleProto::Reject_RejectType_None;
 	bRetryServer = true;
 	qaServerDisconnect->setEnabled(true);
-	g.l->log(Log::Information, tr("Connecting to server %1.").arg(Log::msgColor(Qt::escape(host), Log::Server)));
+	g.l->log(Log::Information, tr("Connecting to server %1.").arg(Log::msgColor(host.toHtmlEscaped(), Log::Server)));
 	g.sh->setConnectionInfo(host, port, user, pw);
 	g.sh->start(QThread::TimeCriticalPriority);
 }
@@ -1163,7 +1133,7 @@ void MainWindow::on_qaServerConnect_triggered(bool autoconnect) {
 		rtLast = MumbleProto::Reject_RejectType_None;
 		bRetryServer = true;
 		qaServerDisconnect->setEnabled(true);
-		g.l->log(Log::Information, tr("Connecting to server %1.").arg(Log::msgColor(Qt::escape(cd->qsServer), Log::Server)));
+		g.l->log(Log::Information, tr("Connecting to server %1.").arg(Log::msgColor(cd->qsServer.toHtmlEscaped(), Log::Server)));
 		g.sh->setConnectionInfo(cd->qsServer, cd->usPort, cd->qsUsername, cd->qsPassword);
 		g.sh->start(QThread::TimeCriticalPriority);
 	}
@@ -1239,7 +1209,7 @@ void MainWindow::on_qaSelfRegister_triggered() {
 		return;
 
 	QMessageBox::StandardButton result;
-	result = QMessageBox::question(this, tr("Register yourself as %1").arg(p->qsName), tr("<p>You are about to register yourself on this server. This action cannot be undone, and your username cannot be changed once this is done. You will forever be known as '%1' on this server.</p><p>Are you sure you want to register yourself?</p>").arg(Qt::escape(p->qsName)), QMessageBox::Yes|QMessageBox::No);
+	result = QMessageBox::question(this, tr("Register yourself as %1").arg(p->qsName), tr("<p>You are about to register yourself on this server. This action cannot be undone, and your username cannot be changed once this is done. You will forever be known as '%1' on this server.</p><p>Are you sure you want to register yourself?</p>").arg(p->qsName.toHtmlEscaped()), QMessageBox::Yes|QMessageBox::No);
 
 	if (result == QMessageBox::Yes)
 		g.sh->registerUser(p->uiSession);
@@ -1351,7 +1321,7 @@ void MainWindow::on_qaServerInformation_triggered() {
 		qsVersion.append(tr("<p>No build information or OS version available</p>"));
 	} else {
 		qsVersion.append(tr("<p>%1 (%2)<br />%3</p>")
-		                 .arg(Qt::escape(g.sh->qsRelease), Qt::escape(g.sh->qsOS), Qt::escape(g.sh->qsOSVersion)));
+		                 .arg(g.sh->qsRelease.toHtmlEscaped(), g.sh->qsOS.toHtmlEscaped(), g.sh->qsOSVersion.toHtmlEscaped()));
 	}
 
 	QString host, uname, pw;
@@ -1403,12 +1373,12 @@ void MainWindow::on_qaServerInformation_triggered() {
 	            "%3"
 	            "<p>%4 ms average latency (%5 deviation)</p>"
 	            "<p>Remote host %6 (port %7)</p>").arg(
-	                  Qt::escape(c->sessionProtocolString()),
+	                  c->sessionProtocolString().toHtmlEscaped(),
 	                  cipherDescription,
 	                  cipherPFSInfo,
 	                  QString::fromLatin1("%1").arg(boost::accumulators::mean(g.sh->accTCP), 0, 'f', 2),
 	                  QString::fromLatin1("%1").arg(sqrt(boost::accumulators::variance(g.sh->accTCP)),0,'f',2),
-	                  Qt::escape(host),
+	                  host.toHtmlEscaped(),
 	                  QString::number(port));
 	if (g.uiMaxUsers) {
 		qsControl += tr("<p>Connected users: %1/%2</p>").arg(ModelItem::c_qhUsers.count()).arg(g.uiMaxUsers);
@@ -1688,9 +1658,9 @@ void MainWindow::on_qaUserRegister_triggered() {
 	QMessageBox::StandardButton result;
 
 	if (session == g.uiSession)
-		result = QMessageBox::question(this, tr("Register yourself as %1").arg(p->qsName), tr("<p>You are about to register yourself on this server. This action cannot be undone, and your username cannot be changed once this is done. You will forever be known as '%1' on this server.</p><p>Are you sure you want to register yourself?</p>").arg(Qt::escape(p->qsName)), QMessageBox::Yes|QMessageBox::No);
+		result = QMessageBox::question(this, tr("Register yourself as %1").arg(p->qsName), tr("<p>You are about to register yourself on this server. This action cannot be undone, and your username cannot be changed once this is done. You will forever be known as '%1' on this server.</p><p>Are you sure you want to register yourself?</p>").arg(p->qsName.toHtmlEscaped()), QMessageBox::Yes|QMessageBox::No);
 	else
-		result = QMessageBox::question(this, tr("Register user %1").arg(p->qsName), tr("<p>You are about to register %1 on the server. This action cannot be undone, the username cannot be changed, and as a registered user, %1 will have access to the server even if you change the server password.</p><p>From this point on, %1 will be authenticated with the certificate currently in use.</p><p>Are you sure you want to register %1?</p>").arg(Qt::escape(p->qsName)), QMessageBox::Yes|QMessageBox::No);
+		result = QMessageBox::question(this, tr("Register user %1").arg(p->qsName), tr("<p>You are about to register %1 on the server. This action cannot be undone, the username cannot be changed, and as a registered user, %1 will have access to the server even if you change the server password.</p><p>From this point on, %1 will be authenticated with the certificate currently in use.</p><p>Are you sure you want to register %1?</p>").arg(p->qsName.toHtmlEscaped()), QMessageBox::Yes|QMessageBox::No);
 
 	if (result == QMessageBox::Yes) {
 		p = ClientUser::get(session);
@@ -1826,7 +1796,7 @@ void MainWindow::on_qaUserCommentReset_triggered() {
 	unsigned int session = p->uiSession;
 
 	int ret = QMessageBox::question(this, QLatin1String("Mumble"),
-	                                tr("Are you sure you want to reset the comment of user %1?").arg(Qt::escape(p->qsName)),
+	                                tr("Are you sure you want to reset the comment of user %1?").arg(p->qsName.toHtmlEscaped()),
 	                                QMessageBox::Yes, QMessageBox::No);
 	if (ret == QMessageBox::Yes) {
 		g.sh->setUserComment(session, QString());
@@ -1842,7 +1812,7 @@ void MainWindow::on_qaUserTextureReset_triggered() {
 	unsigned int session = p->uiSession;
 
 	int ret = QMessageBox::question(this, QLatin1String("Mumble"),
-	                                tr("Are you sure you want to reset the avatar of user %1?").arg(Qt::escape(p->qsName)),
+	                                tr("Are you sure you want to reset the avatar of user %1?").arg(p->qsName.toHtmlEscaped()),
 	                                QMessageBox::Yes, QMessageBox::No);
 	if (ret == QMessageBox::Yes) {
 		g.sh->setUserTexture(session, QByteArray());
@@ -1873,11 +1843,7 @@ void MainWindow::sendChatbarMessage(QString qsText) {
 	ClientUser *p = pmModel->getUser(qtvUsers->currentIndex());
 	Channel *c = pmModel->getChannel(qtvUsers->currentIndex());
 
-#if QT_VERSION >= 0x050000
 	qsText = qsText.toHtmlEscaped();
-#else
-	qsText = Qt::escape(qsText);
-#endif
 	qsText = TextMessage::autoFormat(qsText);
 
 	if (!g.s.bChatBarUseSelection || p == NULL || p->uiSession == g.uiSession) {
@@ -2074,7 +2040,7 @@ void MainWindow::on_qaChannelRemove_triggered() {
 
 	int id = c->iId;
 
-	ret=QMessageBox::question(this, QLatin1String("Mumble"), tr("Are you sure you want to delete %1 and all its sub-channels?").arg(Qt::escape(c->qsName)), QMessageBox::Yes, QMessageBox::No);
+	ret=QMessageBox::question(this, QLatin1String("Mumble"), tr("Are you sure you want to delete %1 and all its sub-channels?").arg(c->qsName.toHtmlEscaped()), QMessageBox::Yes, QMessageBox::No);
 
 	c = Channel::get(id);
 	if (!c)
@@ -2965,7 +2931,7 @@ void MainWindow::serverDisconnected(QAbstractSocket::SocketError err, QString re
 
 	if (! g.sh->qlErrors.isEmpty()) {
 		foreach(QSslError e, g.sh->qlErrors)
-			g.l->log(Log::Warning, tr("SSL Verification failed: %1").arg(Qt::escape(e.errorString())));
+			g.l->log(Log::Warning, tr("SSL Verification failed: %1").arg(e.errorString().toHtmlEscaped()));
 		if (! g.sh->qscCert.isEmpty()) {
 			QSslCertificate c = g.sh->qscCert.at(0);
 			QString basereason;
@@ -2980,7 +2946,7 @@ void MainWindow::serverDisconnected(QAbstractSocket::SocketError err, QString re
 			}
 			QStringList qsl;
 			foreach(QSslError e, g.sh->qlErrors)
-				qsl << QString::fromLatin1("<li>%1</li>").arg(Qt::escape(e.errorString()));
+				qsl << QString::fromLatin1("<li>%1</li>").arg(e.errorString().toHtmlEscaped());
 
 			QMessageBox qmb(QMessageBox::Warning, QLatin1String("Mumble"),
 			                tr("<p>%1</p><ul>%2</ul><p>The specific errors with this certificate are:</p><ol>%3</ol>"
@@ -3013,7 +2979,7 @@ void MainWindow::serverDisconnected(QAbstractSocket::SocketError err, QString re
 
 
 		if (! reason.isEmpty()) {
-			g.l->log(Log::ServerDisconnected, tr("Server connection failed: %1.").arg(Qt::escape(reason)));
+			g.l->log(Log::ServerDisconnected, tr("Server connection failed: %1.").arg(reason.toHtmlEscaped()));
 		}  else {
 			g.l->log(Log::ServerDisconnected, tr("Disconnected from server."));
 		}
@@ -3072,7 +3038,7 @@ void MainWindow::serverDisconnected(QAbstractSocket::SocketError err, QString re
 
 void MainWindow::resolverError(QAbstractSocket::SocketError, QString reason) {
 	if (! reason.isEmpty()) {
-		g.l->log(Log::ServerDisconnected, tr("Server connection failed: %1.").arg(Qt::escape(reason)));
+		g.l->log(Log::ServerDisconnected, tr("Server connection failed: %1.").arg(reason.toHtmlEscaped()));
 	}  else {
 		g.l->log(Log::ServerDisconnected, tr("Server connection failed."));
 	}
@@ -3160,10 +3126,10 @@ void MainWindow::updateChatBar() {
 		if (!g.s.bChatBarUseSelection || c == NULL) // If no channel selected fallback to current one
 			c = ClientUser::get(g.uiSession)->cChannel;
 
-		qteChat->setDefaultText(tr("<center>Type message to channel '%1' here</center>").arg(Qt::escape(c->qsName)));
+		qteChat->setDefaultText(tr("<center>Type message to channel '%1' here</center>").arg(c->qsName.toHtmlEscaped()));
 	} else {
 		// User target
-		qteChat->setDefaultText(tr("<center>Type message to user '%1' here</center>").arg(Qt::escape(p->qsName)));
+		qteChat->setDefaultText(tr("<center>Type message to user '%1' here</center>").arg(p->qsName.toHtmlEscaped()));
 	}
 
 	updateMenuPermissions();
diff --git a/src/mumble/MainWindow.h b/src/mumble/MainWindow.h
index 2616fa5ab..ae8de533d 100644
--- a/src/mumble/MainWindow.h
+++ b/src/mumble/MainWindow.h
@@ -7,16 +7,9 @@
 #define MUMBLE_MUMBLE_MAINWINDOW_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtCore/QPointer>
-# include <QtWidgets/QMainWindow>
-# include <QtWidgets/QSystemTrayIcon>
-#else
-# include <QtCore/QWeakPointer>
-# include <QtGui/QMainWindow>
-# include <QtGui/QSystemTrayIcon>
-#endif
-
+#include <QtCore/QPointer>
+#include <QtWidgets/QMainWindow>
+#include <QtWidgets/QSystemTrayIcon>
 #include <QtNetwork/QAbstractSocket>
 
 #include "CustomElements.h"
@@ -101,13 +94,8 @@ class MainWindow : public QMainWindow, public MessageHandler, public Ui::MainWin
 		/// save when activating the "Save Image As..." context menu item.
 		QTextCursor qtcSaveImageCursor;
 
-#if QT_VERSION >= 0x050000
 		QPointer<Channel> cContextChannel;
 		QPointer<ClientUser> cuContextUser;
-#else
-		QWeakPointer<Channel> cContextChannel;
-		QWeakPointer<ClientUser> cuContextUser;
-#endif
 
 		QPoint qpContextPosition;
 
@@ -126,11 +114,7 @@ class MainWindow : public QMainWindow, public MessageHandler, public Ui::MainWin
 		void openUserLocalVolumeDialog(ClientUser *p);
 
 #ifdef Q_OS_WIN
-#if QT_VERSION >= 0x050000
 		bool nativeEvent(const QByteArray &eventType, void *message, long *result) Q_DECL_OVERRIDE;
-#else
-		bool winEvent(MSG *, long *) Q_DECL_OVERRIDE;
-#endif
 		unsigned int uiNewHardware;
 #endif
 	protected:
diff --git a/src/mumble/ManualPlugin.cpp b/src/mumble/ManualPlugin.cpp
index e0f4fc266..0bdd5a338 100644
--- a/src/mumble/ManualPlugin.cpp
+++ b/src/mumble/ManualPlugin.cpp
@@ -7,11 +7,7 @@
 
 #include <QtCore/QtCore>
 #include <QtGui/QtGui>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QMessageBox>
-#else
-# include <QMessageBox>
-#endif
+#include <QtWidgets/QMessageBox>
 
 #include <QPointer>
 #include "ManualPlugin.h"
diff --git a/src/mumble/ManualPlugin.h b/src/mumble/ManualPlugin.h
index c439d97cf..73f359900 100644
--- a/src/mumble/ManualPlugin.h
+++ b/src/mumble/ManualPlugin.h
@@ -7,15 +7,9 @@
 #define MUMBLE_MUMBLE_MANUALPLUGIN_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QDialog>
-# include <QtWidgets/QGraphicsItem>
-# include <QtWidgets/QGraphicsScene>
-#else
-# include <QDialog>
-# include <QGraphicsItem>
-# include <QGraphicsScene>
-#endif
+#include <QtWidgets/QDialog>
+#include <QtWidgets/QGraphicsItem>
+#include <QtWidgets/QGraphicsScene>
 
 #include "ui_ManualPlugin.h"
 
diff --git a/src/mumble/Messages.cpp b/src/mumble/Messages.cpp
index b6f210e5a..1a1c9d3d3 100644
--- a/src/mumble/Messages.cpp
+++ b/src/mumble/Messages.cpp
@@ -83,7 +83,7 @@ void MainWindow::msgReject(const MumbleProto::Reject &msg) {
 			reason = tr("Your account information can not be verified currently. Please try again later");
 			break;
 		default:
-			reason = Qt::escape(u8(msg.reason()));
+			reason = u8(msg.reason()).toHtmlEscaped();
 			break;
 	}
 
@@ -138,7 +138,7 @@ void MainWindow::msgServerSync(const MumbleProto::ServerSync &msg) {
 	connect(user, SIGNAL(prioritySpeakerStateChanged()), this, SLOT(userStateChanged()));
 	connect(user, SIGNAL(recordingStateChanged()), this, SLOT(userStateChanged()));
 	
-	qstiIcon->setToolTip(tr("Mumble: %1").arg(Qt::escape(Channel::get(0)->qsName)));
+	qstiIcon->setToolTip(tr("Mumble: %1").arg(Channel::get(0)->qsName.toHtmlEscaped()));
 
 	// Update QActions and menues
 	on_qmServer_aboutToShow();
@@ -205,7 +205,7 @@ void MainWindow::msgPermissionDenied(const MumbleProto::PermissionDenied &msg) {
 					g.s.bTTS = true;
 					quint32 oflags = g.s.qmMessages.value(Log::PermissionDenied);
 					g.s.qmMessages[Log::PermissionDenied] = (oflags | Settings::LogTTS) & (~Settings::LogSoundfile);
-					g.l->log(Log::PermissionDenied, QString::fromUtf8(g.ccHappyEaster + 39).arg(Qt::escape(g.s.qsUsername)));
+					g.l->log(Log::PermissionDenied, QString::fromUtf8(g.ccHappyEaster + 39).arg(g.s.qsUsername.toHtmlEscaped()));
 					g.s.qmMessages[Log::PermissionDenied] = oflags;
 					g.s.bDeaf = bold;
 					g.s.bTTS = bold2;
@@ -230,7 +230,7 @@ void MainWindow::msgPermissionDenied(const MumbleProto::PermissionDenied &msg) {
 			break;
 		case MumbleProto::PermissionDenied_DenyType_UserName: {
 				if (msg.has_name())
-					g.l->log(Log::PermissionDenied, tr("Invalid username: %1.").arg(Qt::escape(u8(msg.name()))));
+					g.l->log(Log::PermissionDenied, tr("Invalid username: %1.").arg(u8(msg.name()).toHtmlEscaped()));
 				else
 					g.l->log(Log::PermissionDenied, tr("Invalid username."));
 			}
@@ -249,7 +249,7 @@ void MainWindow::msgPermissionDenied(const MumbleProto::PermissionDenied &msg) {
 			break;
 		default: {
 				if (msg.has_reason())
-					g.l->log(Log::PermissionDenied, tr("Denied: %1.").arg(Qt::escape(u8(msg.reason()))));
+					g.l->log(Log::PermissionDenied, tr("Denied: %1.").arg(u8(msg.reason()).toHtmlEscaped()));
 				else
 					g.l->log(Log::PermissionDenied, tr("Permission denied."));
 			}
@@ -575,7 +575,7 @@ void MainWindow::msgUserRemove(const MumbleProto::UserRemove &msg) {
 	ACTOR_INIT;
 	SELF_INIT;
 
-	QString reason = Qt::escape(u8(msg.reason()));
+	QString reason = u8(msg.reason()).toHtmlEscaped();
 
 	if (pDst == pSelf) {
 		bRetryServer = false;
diff --git a/src/mumble/MumbleApplication.cpp b/src/mumble/MumbleApplication.cpp
index c338fc805..e90f0ec8d 100644
--- a/src/mumble/MumbleApplication.cpp
+++ b/src/mumble/MumbleApplication.cpp
@@ -91,7 +91,6 @@ static bool gswForward(MSG *msg) {
 	return false;
 }
 
-# if QT_VERSION >= 0x050000
 bool MumbleApplication::nativeEventFilter(const QByteArray &, void *message, long *) {
 	MSG *msg = reinterpret_cast<MSG *>(message);
 	if (QThread::currentThread() == thread()) {
@@ -102,15 +101,4 @@ bool MumbleApplication::nativeEventFilter(const QByteArray &, void *message, lon
 	}
 	return false;
 }
-# else
-bool MumbleApplication::winEventFilter(MSG *msg, long *result) {
-	if (QThread::currentThread() == thread()) {
-		bool suppress = gswForward(msg);
-		if (suppress) {
-			return true;
-		}
-	}
-	return QApplication::winEventFilter(msg, result);
-}
-# endif
 #endif
diff --git a/src/mumble/MumbleApplication.h b/src/mumble/MumbleApplication.h
index a67f62f61..cfe5a3031 100644
--- a/src/mumble/MumbleApplication.h
+++ b/src/mumble/MumbleApplication.h
@@ -9,14 +9,14 @@
 #include <QApplication>
 #include <QUrl>
 
-#if QT_VERSION >= 0x050000 && defined(Q_OS_WIN)
-# include <QAbstractNativeEventFilter>
+#ifdef Q_OS_WIN
+#include <QAbstractNativeEventFilter>
 #endif
 
 /**
  * @brief Implements custom system shutdown behavior as well as event filtering.
  */
-#if QT_VERSION >= 0x050000 && defined(Q_OS_WIN)
+#ifdef Q_OS_WIN
 class MumbleApplication : public QApplication, public QAbstractNativeEventFilter {
 #else
 class MumbleApplication : public QApplication {
@@ -50,11 +50,7 @@ class MumbleApplication : public QApplication {
 
 		bool event(QEvent *e) Q_DECL_OVERRIDE;
 #ifdef Q_OS_WIN
-# if QT_VERSION >= 0x050000
 		bool nativeEventFilter(const QByteArray &eventType, void *message, long *result) Q_DECL_OVERRIDE;
-# else
-		bool winEventFilter(MSG *msg, long *result) Q_DECL_OVERRIDE;
-# endif
 #endif
 		
 		QUrl quLaunchURL;
diff --git a/src/mumble/Overlay.cpp b/src/mumble/Overlay.cpp
index 62c77b673..2b47db766 100644
--- a/src/mumble/Overlay.cpp
+++ b/src/mumble/Overlay.cpp
@@ -141,12 +141,8 @@ OverlayAppInfo OverlayAppInfo::applicationInfoForId(const QString &identifier) {
 	HINSTANCE qWinAppInstValue = GetModuleHandle(NULL);
 	HICON icon = ExtractIcon(qWinAppInstValue, identifier.toStdWString().c_str(), 0);
 	if (icon) {
-#if QT_VERSION >= 0x050000
 		extern QPixmap qt_pixmapFromWinHICON(HICON icon);
 		qiAppIcon = QIcon(qt_pixmapFromWinHICON(icon));
-#else
-		qiAppIcon = QIcon(QPixmap::fromWinHICON(icon));
-#endif
 		DestroyIcon(icon);
 	}
 #endif
@@ -220,7 +216,7 @@ Overlay::Overlay() : QObject() {
 #endif
 
 	if (! qlsServer->listen(pipepath)) {
-		QMessageBox::warning(NULL, QLatin1String("Mumble"), tr("Failed to create communication with overlay at %2: %1. No overlay will be available.").arg(Qt::escape(qlsServer->errorString()), Qt::escape(pipepath)), QMessageBox::Ok, QMessageBox::NoButton);
+		QMessageBox::warning(NULL, QLatin1String("Mumble"), tr("Failed to create communication with overlay at %2: %1. No overlay will be available.").arg(qlsServer->errorString().toHtmlEscaped(), pipepath.toHtmlEscaped()), QMessageBox::Ok, QMessageBox::NoButton);
 	} else {
 		qWarning() << "Overlay: Listening on" << qlsServer->fullServerName();
 		connect(qlsServer, SIGNAL(newConnection()), this, SLOT(newConnection()));
diff --git a/src/mumble/Overlay.h b/src/mumble/Overlay.h
index 55dd320d1..c334b9e53 100644
--- a/src/mumble/Overlay.h
+++ b/src/mumble/Overlay.h
@@ -9,11 +9,7 @@
 #include <QtCore/QtGlobal>
 #include <QtCore/QUrl>
 #include <QtNetwork/QLocalSocket>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QGraphicsItem>
-#else
-# include <QtGui/QGraphicsItem>
-#endif
+#include <QtWidgets/QGraphicsItem>
 
 #include "ConfigDialog.h"
 #include "OverlayText.h"
diff --git a/src/mumble/OverlayClient.cpp b/src/mumble/OverlayClient.cpp
index 735d6c88e..bd369edd9 100644
--- a/src/mumble/OverlayClient.cpp
+++ b/src/mumble/OverlayClient.cpp
@@ -137,19 +137,11 @@ void OverlayClient::updateMouse() {
 	QPixmap pm;
 
 	HICON c = ::GetCursor();
-#if QT_VERSION < 0x050000
-	if (c == NULL)
-		c = qgv.viewport()->cursor().handle();
-#endif
-
 	ICONINFO info;
 	ZeroMemory(&info, sizeof(info));
 	if (c != NULL && ::GetIconInfo(c, &info)) {
-#if QT_VERSION >= 0x050000
 		extern QPixmap qt_pixmapFromWinHBITMAP(HBITMAP bitmap, int format = 0);
-#else
-# define qt_pixmapFromWinHBITMAP(bmp) QPixmap::fromWinHBITMAP(bmp)
-#endif
+
 		if (info.hbmColor) {
 			pm = qt_pixmapFromWinHBITMAP(info.hbmColor);
 			pm.setMask(QBitmap(qt_pixmapFromWinHBITMAP(info.hbmMask)));
@@ -195,19 +187,11 @@ void OverlayClient::updateMouse() {
 }
 #endif
 
-#if QT_VERSION < 0x050000 && (defined(Q_OS_WIN) || defined(Q_OS_MAC))
-extern bool Q_GUI_EXPORT qt_use_native_dialogs;
-#endif
-
 // Qt gets very very unhappy if we embed or unmbed the widget that an event is called from.
 // This means that if any modal dialog is open, we'll be in a event loop of an object
 // that we're about to reparent.
 
 void OverlayClient::showGui() {
-#if defined(QT3_SUPPORT) || (defined(Q_OS_WIN) && QT_VERSION < 0x050000)
-	if (QCoreApplication::loopLevel() > 1)
-		return;
-#else
 	int count = 0;
 
 	{
@@ -221,7 +205,6 @@ void OverlayClient::showGui() {
 	// If there's more than one window up, we're likely deep in a message loop.
 	if (count > 1)
 		return;
-#endif
 
 	g.ocIntercept = this;
 
@@ -294,10 +277,6 @@ outer:
 
 	setupScene(true);
 
-#if QT_VERSION < 0x050000 && (defined(Q_OS_WIN) || defined(Q_OS_MAC))
-	qt_use_native_dialogs = false;
-#endif
-
 	OverlayMsg om;
 	om.omh.uiMagic = OVERLAY_MAGIC_NUMBER;
 	om.omh.uiType = OVERLAY_MSGTYPE_INTERACTIVE;
@@ -309,14 +288,6 @@ outer:
 }
 
 void OverlayClient::hideGui() {
-#if defined(QT3_SUPPORT) || (defined(Q_OS_WIN) && QT_VERSION < 0x050000)
-	if (QCoreApplication::loopLevel() > 1) {
-		QCoreApplication::exit_loop();
-		QMetaObject::invokeMethod(this, "hideGui", Qt::QueuedConnection);
-		return;
-	}
-#endif
-
 	ougUsers.bShowExamples = false;
 
 	QList<QWidget *> widgetlist;
@@ -367,9 +338,6 @@ void OverlayClient::hideGui() {
 	setupScene(false);
 
 	qgv.setAttribute(Qt::WA_WState_Hidden, true);
-#if QT_VERSION < 0x050000 && (defined(Q_OS_WIN) || defined(Q_OS_MAC))
-	qt_use_native_dialogs = true;
-#endif
 
 	OverlayMsg om;
 	om.omh.uiMagic = OVERLAY_MAGIC_NUMBER;
diff --git a/src/mumble/OverlayEditorScene.h b/src/mumble/OverlayEditorScene.h
index d9cdf8e25..329db34c9 100644
--- a/src/mumble/OverlayEditorScene.h
+++ b/src/mumble/OverlayEditorScene.h
@@ -7,11 +7,7 @@
 #define MUMBLE_MUMBLE_OVERLAYEDITORSCENE_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QGraphicsScene>
-#else
-# include <QtGui/QGraphicsScene>
-#endif
+#include <QtWidgets/QGraphicsScene>
 
 #include "Settings.h"
 
diff --git a/src/mumble/OverlayPositionableItem.h b/src/mumble/OverlayPositionableItem.h
index ae13be676..5ade1a071 100644
--- a/src/mumble/OverlayPositionableItem.h
+++ b/src/mumble/OverlayPositionableItem.h
@@ -7,11 +7,7 @@
 #define MUMBLE_MUMBLE_OVERLAYPOSITIONABLEITEM_H
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QGraphicsItem>
-#else
-# include <QtGui/QGraphicsItem>
-#endif
+#include <QtWidgets/QGraphicsItem>
 
 class OverlayPositionableItem : public QObject, public QGraphicsPixmapItem {
 	Q_OBJECT
diff --git a/src/mumble/Overlay_macx.mm b/src/mumble/Overlay_macx.mm
index 0f1994692..9aca57298 100644
--- a/src/mumble/Overlay_macx.mm
+++ b/src/mumble/Overlay_macx.mm
@@ -212,13 +212,6 @@ void OverlayClient::updateMouse() {
 				cgimg = [(NSBitmapImageRep *)rep CGImage];
 			}
 		}
-
-#if QT_VERSION < 0x050000
-		if (cgimg) {
-			pm = QPixmap::fromMacCGImageRef(cgimg);
-			qmCursors.insert(csShape, pm);
-		}
-#endif
 	}
 
 	NSPoint p = [cursor hotSpot];
diff --git a/src/mumble/Plugins.cpp b/src/mumble/Plugins.cpp
index fca8876bf..1addf2643 100644
--- a/src/mumble/Plugins.cpp
+++ b/src/mumble/Plugins.cpp
@@ -73,13 +73,8 @@ struct PluginFetchMeta {
 PluginConfig::PluginConfig(Settings &st) : ConfigWidget(st) {
 	setupUi(this);
 
-#if QT_VERSION >= 0x050000
 	qtwPlugins->header()->setSectionResizeMode(0, QHeaderView::Stretch);
 	qtwPlugins->header()->setSectionResizeMode(1, QHeaderView::ResizeToContents);
-#else
-	qtwPlugins->header()->setResizeMode(0, QHeaderView::Stretch);
-	qtwPlugins->header()->setResizeMode(1, QHeaderView::ResizeToContents);
-#endif
 
 	refillPluginList();
 }
@@ -177,7 +172,7 @@ void PluginConfig::refillPluginList() {
 		i->setCheckState(1, pi->enabled ? Qt::Checked : Qt::Unchecked);
 		i->setText(0, pi->description);
 		if (pi->p->longdesc)
-			i->setToolTip(0, Qt::escape(QString::fromStdWString(pi->p->longdesc())));
+			i->setToolTip(0, QString::fromStdWString(pi->p->longdesc()).toHtmlEscaped());
 		i->setData(0, Qt::UserRole, pi->filename);
 	}
 	qtwPlugins->setCurrentItem(qtwPlugins->topLevelItem(0));
@@ -430,7 +425,7 @@ void Plugins::on_Timer_timeout() {
 	QReadLocker lock(&qrwlPlugins);
 
 	if (prevlocked) {
-		g.l->log(Log::Information, tr("%1 lost link.").arg(Qt::escape(prevlocked->shortname)));
+		g.l->log(Log::Information, tr("%1 lost link.").arg(prevlocked->shortname.toHtmlEscaped()));
 		prevlocked = NULL;
 	}
 
@@ -553,7 +548,7 @@ void Plugins::on_Timer_timeout() {
 	if (pi->enabled) {
 		if (pi->p2 ? pi->p2->trylock(pids) : pi->p->trylock()) {
 			pi->shortname = QString::fromStdWString(pi->p->shortname);
-			g.l->log(Log::Information, tr("%1 linked.").arg(Qt::escape(pi->shortname)));
+			g.l->log(Log::Information, tr("%1 linked.").arg(pi->shortname.toHtmlEscaped()));
 			pi->locked = true;
 			bUnlink = false;
 			locked = pi;
@@ -586,16 +581,10 @@ void Plugins::checkUpdates() {
 
 
 #ifdef QT_NO_DEBUG
-#if QT_VERSION >= 0x050000
 	QUrlQuery query;
 	query.setQueryItems(queryItems);
 	url.setQuery(query);
-#else
-	for (int i = 0; i < queryItems.size(); i++) {
-		const QPair<QString, QString> &queryPair = queryItems.at(i);
-		url.addQueryItem(queryPair.first, queryPair.second);
-	}
-#endif
+
 	WebFetch::fetch(QLatin1String("update"), url, this, SLOT(fetchedUpdatePAPlugins(QByteArray,QUrl)));
 #else
 	g.mw->msgBox(tr("Skipping plugin update in debug mode."));
@@ -766,15 +755,15 @@ void Plugins::fetchedPAPluginDL(QByteArray data, QUrl url) {
 				if (f.open(QIODevice::WriteOnly)) {
 					f.write(data);
 					f.close();
-					g.mw->msgBox(tr("Downloaded new or updated plugin to %1.").arg(Qt::escape(f.fileName())));
+					g.mw->msgBox(tr("Downloaded new or updated plugin to %1.").arg(f.fileName().toHtmlEscaped()));
 				} else {
 					f.setFileName(qsUserPlugins + QLatin1String("/") + fname);
 					if (f.open(QIODevice::WriteOnly)) {
 						f.write(data);
 						f.close();
-						g.mw->msgBox(tr("Downloaded new or updated plugin to %1.").arg(Qt::escape(f.fileName())));
+						g.mw->msgBox(tr("Downloaded new or updated plugin to %1.").arg(f.fileName().toHtmlEscaped()));
 					} else {
-						g.mw->msgBox(tr("Failed to install new plugin to %1.").arg(Qt::escape(f.fileName())));
+						g.mw->msgBox(tr("Failed to install new plugin to %1.").arg(f.fileName().toHtmlEscaped()));
 					}
 				}
 
diff --git a/src/mumble/RichTextEditor.cpp b/src/mumble/RichTextEditor.cpp
index 20c5d5ace..15f96eabe 100644
--- a/src/mumble/RichTextEditor.cpp
+++ b/src/mumble/RichTextEditor.cpp
@@ -130,13 +130,9 @@ void RichTextHtmlEdit::insertFromMimeData(const QMimeData *source) {
 	if (! uri.isEmpty()) {
 		if (title.isEmpty())
 			title = uri;
-#if QT_VERSION >= 0x050000
+
 		uri = uri.toHtmlEscaped();
 		title = title.toHtmlEscaped();
-#else
-		uri = Qt::escape(uri);
-		title = Qt::escape(title);
-#endif
 
 		insertHtml(QString::fromLatin1("<a href=\"%1\">%2</a>").arg(uri, title));
 		return;
@@ -163,11 +159,7 @@ QString RichTextEditorLink::text() const {
 	QUrl url(qleUrl->text(), QUrl::StrictMode);
 	QString txt = qleText->text();
 
-#if QT_VERSION >= 0x050000
 	txt = txt.toHtmlEscaped();
-#else
-	txt = Qt::escape(txt);
-#endif
 
 	if (url.isValid() && ! url.isRelative() && ! txt.isEmpty()) {
 		return QString::fromLatin1("<a href=\"%1\">%2</a>").arg(url.toString(), txt);
diff --git a/src/mumble/RichTextEditor.h b/src/mumble/RichTextEditor.h
index 5d43c98e6..ce73c6b21 100644
--- a/src/mumble/RichTextEditor.h
+++ b/src/mumble/RichTextEditor.h
@@ -7,11 +7,7 @@
 #define MUMBLE_MUMBLE_RICHTEXTEDITOR_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QTextEdit>
-#else
-# include <QtGui/QTextEdit>
-#endif
+#include <QtWidgets/QTextEdit>
 
 class LogDocument;
 
diff --git a/src/mumble/ServerHandler.cpp b/src/mumble/ServerHandler.cpp
index 6498e1391..b5606acef 100644
--- a/src/mumble/ServerHandler.cpp
+++ b/src/mumble/ServerHandler.cpp
@@ -379,11 +379,10 @@ void ServerHandler::run() {
 		// In Qt 5.4, QSsl::SecureProtocols is equivalent
 		// to "TLSv1.0 or later", which we require.
 		qtsSock->setProtocol(QSsl::SecureProtocols);
-	#elif QT_VERSION >= 0x050000
-		qtsSock->setProtocol(QSsl::TlsV1_0);
 	#else
-		qtsSock->setProtocol(QSsl::TlsV1);
+		qtsSock->setProtocol(QSsl::TlsV1_0);
 	#endif
+
 		qtsSock->connectToHost(saTargetServer.host.toAddress(), saTargetServer.port);
 
 		tTimestamp.restart();
diff --git a/src/mumble/Settings.cpp b/src/mumble/Settings.cpp
index 298aab6ee..008bc3e2e 100644
--- a/src/mumble/Settings.cpp
+++ b/src/mumble/Settings.cpp
@@ -282,11 +282,7 @@ Settings::Settings() {
 	bPluginCheck = true;
 #endif
 
-#if QT_VERSION >= 0x050000
 	qsImagePath = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation);
-#else
-	qsImagePath = QDesktopServices::storageLocation(QDesktopServices::PicturesLocation);
-#endif
 
 	ceExpand = ChannelsWithUsers;
 	ceChannelDrag = Ask;
@@ -379,11 +375,7 @@ Settings::Settings() {
 	bHighContrast = false;
 
 	// Recording
-#if QT_VERSION >= 0x050000
 	qsRecordingPath = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
-#else
-	qsRecordingPath = QDesktopServices::storageLocation(QDesktopServices::DocumentsLocation);
-#endif
 	qsRecordingFile = QLatin1String("Mumble-%date-%time-%host-%user");
 	rmRecordingMode = RecordingMixdown;
 	iRecordingFormat = 0;
diff --git a/src/mumble/SocketRPC.cpp b/src/mumble/SocketRPC.cpp
index 8a220b928..86234c5af 100644
--- a/src/mumble/SocketRPC.cpp
+++ b/src/mumble/SocketRPC.cpp
@@ -176,13 +176,9 @@ void SocketRPCClient::processXml() {
 				u.setPort(port);
 				u.setUserName(user);
 
-#if QT_VERSION >= 0x050000
 				QUrlQuery query;
 				query.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
 				u.setQuery(query);
-#else
-				u.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
-#endif
 
 				QStringList path;
 				Channel *c = ClientUser::get(g.uiSession)->cChannel;
diff --git a/src/mumble/TaskList.cpp b/src/mumble/TaskList.cpp
index 58e37dedc..ffde41380 100644
--- a/src/mumble/TaskList.cpp
+++ b/src/mumble/TaskList.cpp
@@ -39,15 +39,10 @@ void TaskList::addToRecentList(QString name, QString user, QString host, int por
 	url.setHost(host);
 	url.setPort(port);
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query;
 	query.addQueryItem(QLatin1String("title"), name);
 	query.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
 	url.setQuery(query);
-#else
-	url.addQueryItem(QLatin1String("title"), name);
-	url.addQueryItem(QLatin1String("version"), QLatin1String("1.2.0"));
-#endif
 
 	QSettings settings(QLatin1String("HKEY_CLASSES_ROOT"), QSettings::NativeFormat);
 
diff --git a/src/mumble/UserEdit.cpp b/src/mumble/UserEdit.cpp
index d1305dcf9..972bdaf9f 100644
--- a/src/mumble/UserEdit.cpp
+++ b/src/mumble/UserEdit.cpp
@@ -37,20 +37,12 @@ UserEdit::UserEdit(const MumbleProto::UserList &userList, QWidget *p)
 
 	qtvUserList->setFocus();
 	qtvUserList->setContextMenuPolicy(Qt::CustomContextMenu);
-
-#if QT_VERSION >= 0x050000
 	qtvUserList->header()->setSectionResizeMode(UserListModel::COL_NICK, QHeaderView::Stretch);
+
 	if (!m_model->isLegacy()) {
 		qtvUserList->header()->setSectionResizeMode(UserListModel::COL_INACTIVEDAYS, QHeaderView::ResizeToContents);
 		qtvUserList->header()->setSectionResizeMode(UserListModel::COL_LASTCHANNEL, QHeaderView::Stretch);
 	}
-#else
-	qtvUserList->header()->setResizeMode(UserListModel::COL_NICK, QHeaderView::Stretch);
-	if (!m_model->isLegacy()) {
-		qtvUserList->header()->setResizeMode(UserListModel::COL_INACTIVEDAYS, QHeaderView::ResizeToContents);
-		qtvUserList->header()->setResizeMode(UserListModel::COL_LASTCHANNEL, QHeaderView::Stretch);
-	}
-#endif
 
 	if (m_model->isLegacy()) {
 		qlInactive->hide();
diff --git a/src/mumble/UserInformation.cpp b/src/mumble/UserInformation.cpp
index 4fb5d2ce9..c93c7c544 100644
--- a/src/mumble/UserInformation.cpp
+++ b/src/mumble/UserInformation.cpp
@@ -21,14 +21,12 @@ static QString decode_utf8_qssl_string(const QString &input) {
 	return QUrl::fromPercentEncoding(i.replace(QLatin1String("\\x"), QLatin1String("%")).toLatin1());
 }
 
-#if QT_VERSION >= 0x050000
 static QString decode_utf8_qssl_string(const QStringList &list) {
 	if (list.count() > 0) {
 		return decode_utf8_qssl_string(list.at(0));
 	}
 	return QString();
 }
-#endif
 
 UserInformation::UserInformation(const MumbleProto::UserStats &msg, QWidget *p) : QDialog(p) {
 	setupUi(this);
@@ -115,12 +113,7 @@ void UserInformation::update(const MumbleProto::UserStats &msg) {
 			qpbCertificate->setEnabled(true);
 
 			const QSslCertificate &cert = qlCerts.last();
-
-#if QT_VERSION >= 0x050000
 			const QMultiMap<QSsl::AlternativeNameEntryType, QString> &alts = cert.subjectAlternativeNames();
-#else
-			const QMultiMap<QSsl::AlternateNameEntryType, QString> &alts = cert.alternateSubjectNames();
-#endif
 			if (alts.contains(QSsl::EmailEntry))
 				qlCertificate->setText(QStringList(alts.values(QSsl::EmailEntry)).join(tr(", ")));
 			else
diff --git a/src/mumble/UserListModel.cpp b/src/mumble/UserListModel.cpp
index 2f5d41596..6534e80a8 100644
--- a/src/mumble/UserListModel.cpp
+++ b/src/mumble/UserListModel.cpp
@@ -93,7 +93,7 @@ QVariant UserListModel::data(const QModelIndex &dataIndex, int role) const {
 		switch (dataIndex.column()) {
 			case COL_INACTIVEDAYS: return tr("Last seen: %1").arg(user.last_seen().empty() ?
 				                                                      tr("Never")
-				                                                    : Qt::escape(u8(user.last_seen())));
+				                                                    : u8(user.last_seen()).toHtmlEscaped());
 			case COL_LASTCHANNEL:  return tr("Channel ID: %1").arg(user.last_channel());
 			default:               return QVariant();
 		}
diff --git a/src/mumble/UserView.cpp b/src/mumble/UserView.cpp
index fdcd5afd2..121808376 100644
--- a/src/mumble/UserView.cpp
+++ b/src/mumble/UserView.cpp
@@ -41,12 +41,7 @@ void UserDelegate::paint(QPainter * painter, const QStyleOptionViewItem &option,
 
 	painter->save();
 
-#if QT_VERSION >= 0x050000
 	QStyleOptionViewItem o = option;
-#else
-	QStyleOptionViewItemV4 o = option;
-#endif
-
 	initStyleOption(&o, index);
 
 	QStyle *style = o.widget->style();
@@ -375,12 +370,7 @@ void UserView::updateChannel(const QModelIndex &idx) {
 	}
 }
 
-#if QT_VERSION >= 0x050000
-void UserView::dataChanged ( const QModelIndex & topLeft, const QModelIndex & bottomRight, const QVector<int> &)
-#else
-void UserView::dataChanged ( const QModelIndex & topLeft, const QModelIndex & bottomRight)
-#endif
-{
+void UserView::dataChanged ( const QModelIndex & topLeft, const QModelIndex & bottomRight, const QVector<int> &) {
 	UserModel *um = static_cast<UserModel *>(model());
 	int nRowCount = um->rowCount();
 	int i;
@@ -389,4 +379,3 @@ void UserView::dataChanged ( const QModelIndex & topLeft, const QModelIndex & bo
 
 	QTreeView::dataChanged(topLeft,bottomRight);
 }
-
diff --git a/src/mumble/UserView.h b/src/mumble/UserView.h
index f84d9cd03..8c50cd82b 100644
--- a/src/mumble/UserView.h
+++ b/src/mumble/UserView.h
@@ -7,13 +7,8 @@
 #define MUMBLE_MUMBLE_USERVIEW_H_
 
 #include <QtCore/QtGlobal>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QStyledItemDelegate>
-# include <QtWidgets/QTreeView>
-#else 
-# include <QtGui/QStyledItemDelegate>
-# include <QtGui/QTreeView>
-#endif
+#include <QtWidgets/QStyledItemDelegate>
+#include <QtWidgets/QTreeView>
 
 #include "Timer.h"
 
@@ -52,12 +47,7 @@ class UserView : public QTreeView {
 	public:
 		UserView(QWidget *);
 		void keyboardSearch(const QString &search) Q_DECL_OVERRIDE;
-#if QT_VERSION >= 0x050000
 		void dataChanged(const QModelIndex & topLeft, const QModelIndex & bottomRight, const QVector<int> & roles = QVector<int> ()) Q_DECL_OVERRIDE;
-#else
-		void dataChanged(const QModelIndex & topLeft, const QModelIndex & bottomRight) Q_DECL_OVERRIDE;
-#endif
-		
 	public slots:
 		void nodeActivated(const QModelIndex &idx);
 		void selectSearchResult();
diff --git a/src/mumble/VersionCheck.cpp b/src/mumble/VersionCheck.cpp
index a14af8ab6..b2c1a25b3 100644
--- a/src/mumble/VersionCheck.cpp
+++ b/src/mumble/VersionCheck.cpp
@@ -67,16 +67,10 @@ VersionCheck::VersionCheck(bool autocheck, QObject *p, bool focus) : QObject(p)
 		}
 	}
 
-#if QT_VERSION >= 0x050000
 	QUrlQuery query;
 	query.setQueryItems(queryItems);
 	url.setQuery(query);
-#else
-	for (int i = 0; i < queryItems.size(); i++) {
-		const QPair<QString, QString> &queryPair = queryItems.at(i);
-		url.addQueryItem(queryPair.first, queryPair.second);
-	}
-#endif
+
 	WebFetch::fetch(QLatin1String("update"), url, this, SLOT(fetched(QByteArray,QUrl)));
 }
 
@@ -173,7 +167,7 @@ void VersionCheck::fetched(QByteArray a, QUrl url) {
 							file.remove();
 						}
 					} else {
-						g.mw->msgBox(tr("Downloading new snapshot from %1 to %2").arg(Qt::escape(fetch.toString()), Qt::escape(filename)));
+						g.mw->msgBox(tr("Downloading new snapshot from %1 to %2").arg(fetch.toString().toHtmlEscaped(), filename.toHtmlEscaped()));
 						WebFetch::fetch(QLatin1String("dl"), fetch, this, SLOT(fetched(QByteArray,QUrl)));
 						return;
 					}
diff --git a/src/mumble/ViewCert.cpp b/src/mumble/ViewCert.cpp
index 6aa6d539f..3768b4396 100644
--- a/src/mumble/ViewCert.cpp
+++ b/src/mumble/ViewCert.cpp
@@ -18,7 +18,6 @@ static QString decode_utf8_qssl_string(const QString &input) {
 	return QUrl::fromPercentEncoding(i.replace(QLatin1String("\\x"), QLatin1String("%")).toLatin1());
 }
 
-#if QT_VERSION >= 0x050000
 static QStringList processQSslCertificateInfo(QStringList in) {
 	QStringList list;
 	foreach (QString str, in) {
@@ -26,13 +25,6 @@ static QStringList processQSslCertificateInfo(QStringList in) {
 	}
 	return list;
 }
-#else
-static QStringList processQSslCertificateInfo(QString in) {
-	QStringList out;
-	out << decode_utf8_qssl_string(in);
-	return out;
-}
-#endif
 
 static void addQSslCertificateInfo(QStringList &l, const QString &label, const QStringList &items) {
 	foreach (const QString &item, items) {
@@ -132,17 +124,10 @@ void ViewCert::on_Chain_currentRowChanged(int idx) {
 	l << tr("Serial: %1").arg(QString::fromLatin1(c.serialNumber().toHex()));
 	l << tr("Public Key: %1 bits %2").arg(c.publicKey().length()).arg((c.publicKey().algorithm() == QSsl::Rsa) ? tr("RSA") : tr("DSA"));
 	l << tr("Digest (SHA-1): %1").arg(prettifyDigest(QString::fromLatin1(c.digest(QCryptographicHash::Sha1).toHex())));
-#if QT_VERSION >= 0x050000
 	l << tr("Digest (SHA-256): %1").arg(prettifyDigest(QString::fromLatin1(c.digest(QCryptographicHash::Sha256).toHex())));
-#endif
 
-#if QT_VERSION >= 0x050000
 	const QMultiMap<QSsl::AlternativeNameEntryType, QString> &alts = c.subjectAlternativeNames();
 	QMultiMap<QSsl::AlternativeNameEntryType, QString>::const_iterator i;
-#else
-	const QMultiMap<QSsl::AlternateNameEntryType, QString> &alts = c.alternateSubjectNames();
-	QMultiMap<QSsl::AlternateNameEntryType, QString>::const_iterator i;
-#endif
 
 	for (i=alts.constBegin(); i != alts.constEnd(); ++i) {
 		switch (i.key()) {
diff --git a/src/mumble/ViewCert.h b/src/mumble/ViewCert.h
index ef4875c14..c74162b36 100644
--- a/src/mumble/ViewCert.h
+++ b/src/mumble/ViewCert.h
@@ -9,12 +9,7 @@
 #include <QtCore/QtGlobal>
 #include <QtCore/QObject>
 #include <QtCore/QList>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QDialog>
-#else
-# include <QtGui/QDialog>
-#endif
-
+#include <QtWidgets/QDialog>
 #include <QtNetwork/QSslCertificate>
 
 class QListWidget;
diff --git a/src/mumble/main.cpp b/src/mumble/main.cpp
index b0b810d34..69613fa67 100644
--- a/src/mumble/main.cpp
+++ b/src/mumble/main.cpp
@@ -55,18 +55,6 @@
 // We define a global macro called 'g'. This can lead to issues when included code uses 'g' as a type or parameter name (like protobuf 3.7 does). As such, for now, we have to make this our last include.
 #include "Global.h"
 
-#if defined(USE_STATIC_QT_PLUGINS) && QT_VERSION < 0x050000
-Q_IMPORT_PLUGIN(qtaccessiblewidgets)
-# ifdef Q_OS_WIN
-   Q_IMPORT_PLUGIN(qico)
-# endif
-Q_IMPORT_PLUGIN(qsvg)
-Q_IMPORT_PLUGIN(qsvgicon)
-# ifdef Q_OS_MAC
-   Q_IMPORT_PLUGIN(qicnsicon)
-# endif
-#endif
-
 #ifdef BOOST_NO_EXCEPTIONS
 namespace boost {
 	void throw_exception(std::exception const &) {
@@ -120,7 +108,7 @@ int main(int argc, char **argv) {
 	a.setAttribute(Qt::AA_UseHighDpiPixmaps);
 #endif
 
-#if QT_VERSION >= 0x050000 && defined(Q_OS_WIN)
+#ifdef Q_OS_WIN
 	a.installNativeEventFilter(&a);
 #endif
 
@@ -508,12 +496,7 @@ int main(int argc, char **argv) {
 	g.s.uiUpdateCounter = 2;
 
 	if (! CertWizard::validateCert(g.s.kpCertificate)) {
-#if QT_VERSION >= 0x050000
 		QDir qd(QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation));
-#else
-		QDir qd(QDesktopServices::storageLocation(QDesktopServices::DocumentsLocation));
-#endif
-
 		QFile qf(qd.absoluteFilePath(QLatin1String("MumbleAutomaticCertificateBackup.p12")));
 		if (qf.open(QIODevice::ReadOnly | QIODevice::Unbuffered)) {
 			Settings::KeyPair kp = CertWizard::importCert(qf.readAll());
diff --git a/src/mumble/mumble_pch.hpp b/src/mumble/mumble_pch.hpp
index cabbdc8ac..59d2f3061 100644
--- a/src/mumble/mumble_pch.hpp
+++ b/src/mumble/mumble_pch.hpp
@@ -31,10 +31,7 @@
 
 #include <QtCore/QtCore>
 #include <QtGui/QtGui>
-#if QT_VERSION >= 0x050000
-# include "Qt4Compat.h"
-# include <QtWidgets/QtWidgets>
-#endif
+#include <QtWidgets/QtWidgets>
 
 #include <QtSvg/QtSvg>
 #ifdef USE_DBUS
diff --git a/src/mumble/os_macx.mm b/src/mumble/os_macx.mm
index 616b5251b..e8a42682c 100644
--- a/src/mumble/os_macx.mm
+++ b/src/mumble/os_macx.mm
@@ -60,16 +60,10 @@ static void mumbleMessageOutputQString(QtMsgType type, const QString &msg) {
 	}
 }
 
-#if QT_VERSION < 0x050000
-static void mumbleMessageOutput(QtMsgType type, const char *msg) {
-	mumbleMessageOutputQString(type, QString::fromUtf8(msg));
-}
-#elif QT_VERSION >= 0x050000
 static void mumbleMessageOutputWithContext(QtMsgType type, const QMessageLogContext &ctx, const QString &msg) {
 	Q_UNUSED(ctx);
 	mumbleMessageOutputQString(type, msg);
 }
-#endif
 
 void query_language() {
 	CFPropertyListRef cfaLangs;
@@ -154,11 +148,7 @@ void os_init() {
 		strcat(buff, logpath);
 		fConsole = fopen(buff, "a+");
 		if (fConsole) {
-#if QT_VERSION >= 0x050000
-		qInstallMessageHandler(mumbleMessageOutputWithContext);
-#else
-		qInstallMsgHandler(mumbleMessageOutput);
-#endif
+			qInstallMessageHandler(mumbleMessageOutputWithContext);
 		}
 	}
 
diff --git a/src/mumble/os_unix.cpp b/src/mumble/os_unix.cpp
index dc14de63d..669d907f6 100644
--- a/src/mumble/os_unix.cpp
+++ b/src/mumble/os_unix.cpp
@@ -38,16 +38,10 @@ static void mumbleMessageOutputQString(QtMsgType type, const QString &msg) {
 	}
 }
 
-#if QT_VERSION < 0x050000
-static void mumbleMessageOutput(QtMsgType type, const char *msg) {
-	mumbleMessageOutputQString(type, QString::fromUtf8(msg));
-}
-#elif QT_VERSION >= 0x050000
 static void mumbleMessageOutputWithContext(QtMsgType type, const QMessageLogContext &ctx, const QString &msg) {
 	Q_UNUSED(ctx);
 	mumbleMessageOutputQString(type, msg);
 }
-#endif
 
 void os_init() {
 	// Make a copy of the global LogEmitter, such that
@@ -55,9 +49,5 @@ void os_init() {
 	// of the Global object and its LogEmitter object.
 	le = g.le;
 
-#if QT_VERSION >= 0x050000
 	qInstallMessageHandler(mumbleMessageOutputWithContext);
-#else
-	qInstallMsgHandler(mumbleMessageOutput);
-#endif
 }
diff --git a/src/mumble/os_win.cpp b/src/mumble/os_win.cpp
index ba107c7ef..2633cb929 100644
--- a/src/mumble/os_win.cpp
+++ b/src/mumble/os_win.cpp
@@ -81,18 +81,10 @@ static void mumbleMessageOutputQString(QtMsgType type, const QString &msg) {
 	}
 }
 
-#if QT_VERSION < 0x050000
-static void mumbleMessageOutput(QtMsgType type, const char *msg) {
-	mumbleMessageOutputQString(type, QString::fromUtf8(msg));
-}
-#endif
-
-#if QT_VERSION >= 0x050000
 static void mumbleMessageOutputWithContext(QtMsgType type, const QMessageLogContext &ctx, const QString &msg) {
 	Q_UNUSED(ctx);
 	mumbleMessageOutputQString(type, msg);
 }
-#endif
 
 static LONG WINAPI MumbleUnhandledExceptionFilter(struct _EXCEPTION_POINTERS* ExceptionInfo) {
 	MINIDUMP_EXCEPTION_INFORMATION i;
@@ -269,11 +261,7 @@ void os_init() {
 	fConsole = _wfsopen(console.toStdWString().c_str(), L"a+", _SH_DENYWR);
 
 	if (fConsole) {
-#if QT_VERSION >= 0x050000
 		qInstallMessageHandler(mumbleMessageOutputWithContext);
-#else
-		qInstallMsgHandler(mumbleMessageOutput);
-#endif
 	}
 
 	QString hash;
diff --git a/src/murmur/About.cpp b/src/murmur/About.cpp
index 1a72af15b..18f2c661a 100644
--- a/src/murmur/About.cpp
+++ b/src/murmur/About.cpp
@@ -38,9 +38,9 @@ AboutDialog::AboutDialog(QWidget *p, AboutDialogOptions options) : QDialog(p) {
 	QList<LicenseInfo> thirdPartyLicenses = License::thirdPartyLicenses();
 	foreach(LicenseInfo li, thirdPartyLicenses) {
 		qtb3rdPartyLicense->append(QString::fromLatin1("<h3>%1 (<a href=\"%2\">%2</a>)</h3><pre>%3</pre>")
-				.arg(Qt::escape(li.name))
-				.arg(Qt::escape(li.url))
-				.arg(Qt::escape(li.license)));
+				.arg(li.name.toHtmlEscaped())
+				.arg(li.url.toHtmlEscaped())
+				.arg(li.license.toHtmlEscaped()));
 	}
 
 	qtb3rdPartyLicense->moveCursor(QTextCursor::Start);
diff --git a/src/murmur/About.h b/src/murmur/About.h
index fb21a1708..0467a5b74 100644
--- a/src/murmur/About.h
+++ b/src/murmur/About.h
@@ -8,11 +8,7 @@
 
 #include <QtCore/QtGlobal>
 #include <QtCore/QObject>
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QDialog>
-#else
-# include <QtGui/QDialog>
-#endif
+#include <QtWidgets/QDialog>
 
 enum AboutDialogOptions {
 	AboutDialogOptionsShowAbout,
diff --git a/src/murmur/Cert.cpp b/src/murmur/Cert.cpp
index 3a1fe10b1..80883cca8 100644
--- a/src/murmur/Cert.cpp
+++ b/src/murmur/Cert.cpp
@@ -129,14 +129,11 @@ void Server::initializeCert() {
 #endif
 
 	QString issuer;
-#if QT_VERSION >= 0x050000
+
 	QStringList issuerNames = qscCert.issuerInfo(QSslCertificate::CommonName);
 	if (! issuerNames.isEmpty()) {
 		issuer = issuerNames.first();
 	}
-#else
-	issuer = qscCert.issuerInfo(QSslCertificate::CommonName);
-#endif
 
 	// Really old certs/keys are no good, throw them away so we can
 	// generate a new one below.
diff --git a/src/murmur/Meta.cpp b/src/murmur/Meta.cpp
index 3baac7a7b..f52620167 100644
--- a/src/murmur/Meta.cpp
+++ b/src/murmur/Meta.cpp
@@ -140,11 +140,7 @@ void MetaParams::read(QString fname) {
 		QStringList datapaths;
 
 #if defined(Q_OS_WIN)
-#if QT_VERSION >= 0x050000
 		datapaths << QStandardPaths::writableLocation(QStandardPaths::DataLocation);
-#else
-		datapaths << QDesktopServices::storageLocation(QDesktopServices::DataLocation);
-#endif
 
 		QDir appdir = QDir(QDir::fromNativeSeparators(EnvUtils::getenv(QLatin1String("APPDATA"))));
 		datapaths << appdir.absolutePath() + QLatin1String("/Mumble");
@@ -188,9 +184,8 @@ void MetaParams::read(QString fname) {
 	}
 	QDir::setCurrent(qdBasePath.absolutePath());
 	qsSettings = new QSettings(qsAbsSettingsFilePath, QSettings::IniFormat);
-#if QT_VERSION >= 0x040500
 	qsSettings->setIniCodec("UTF-8");
-#endif
+
 	qWarning("Initializing settings from %s (basepath %s)", qPrintable(qsSettings->fileName()), qPrintable(qdBasePath.absolutePath()));
 
 	QString qsHost = qsSettings->value("host", QString()).toString();
@@ -258,7 +253,6 @@ void MetaParams::read(QString fname) {
 			hasipv4 = true;
 		}
 
-#if QT_VERSION >= 0x050000
 		if (hasipv6) {
 			if (SslServer::hasDualStackSupport() && hasipv4) {
 				qlBind << QHostAddress(QHostAddress::Any);
@@ -271,23 +265,6 @@ void MetaParams::read(QString fname) {
 		if (hasipv4) {
 			qlBind << QHostAddress(QHostAddress::AnyIPv4);
 		}
-#else // QT_VERSION < 0x050000
-		// For Qt 4 AnyIPv6 resulted in a dual stack socket on dual stack
-		// capable systems while Any resulted in an IPv4 only socket. For
-		// Qt 5 this has been reworked so that AnyIPv6/v4 are now exclusive
-		// IPv6/4 sockets while Any is the dual stack socket.
-
-		if (hasipv6) {
-			qlBind << QHostAddress(QHostAddress::AnyIPv6);
-			if (SslServer::hasDualStackSupport() && hasipv4) {
-				hasipv4 = false; // No need to add a separate ipv4 socket
-			}
-		}
-
-		if (hasipv4) {
-			qlBind << QHostAddress(QHostAddress::Any);
-		}
-#endif
 	}
 
 	qsPassword = typeCheckedFromSettings("serverpassword", qsPassword);
@@ -444,9 +421,7 @@ void MetaParams::read(QString fname) {
 
 bool MetaParams::loadSSLSettings() {
 	QSettings updatedSettings(qsAbsSettingsFilePath, QSettings::IniFormat);
-#if QT_VERSION >= 0x040500
 	updatedSettings.setIniCodec("UTF-8");
-#endif
 
 	QString tmpCiphersStr = typeCheckedFromSettings("sslCiphers", qsCiphers);
 
diff --git a/src/murmur/MurmurIce.cpp b/src/murmur/MurmurIce.cpp
index 14d4b336f..8cf319e63 100644
--- a/src/murmur/MurmurIce.cpp
+++ b/src/murmur/MurmurIce.cpp
@@ -123,7 +123,7 @@ static void userToUser(const ::User *p, Murmur::User &mp) {
 	mp.udpPing = u->dUDPPingAvg;
 	mp.tcpPing = u->dTCPPingAvg;
 
-	mp.tcponly = QAtomicIntLoad(u->aiUdpFlag) == 0;
+	mp.tcponly = u->aiUdpFlag.load() == 0;
 
 	::Murmur::NetAddress addr(16, 0);
 	const Q_IPV6ADDR &a = u->haAddress.qip6;
diff --git a/src/murmur/Server.cpp b/src/murmur/Server.cpp
index 84e5b4ebe..15037c5c5 100644
--- a/src/murmur/Server.cpp
+++ b/src/murmur/Server.cpp
@@ -95,11 +95,7 @@ bool SslServer::hasDualStackSupport() {
 	return result;
 }
 
-#if QT_VERSION >= 0x050000
 void SslServer::incomingConnection(qintptr v) {
-#else
-void SslServer::incomingConnection(int v) {
-#endif
 	QSslSocket *s = new QSslSocket(this);
 	s->setSocketDescriptor(v);
 	qlSockets.append(s);
@@ -934,7 +930,7 @@ bool Server::checkDecrypt(ServerUser *u, const char *encrypt, char *plain, unsig
 }
 
 void Server::sendMessage(ServerUser *u, const char *data, int len, QByteArray &cache, bool force) {
-	if ((QAtomicIntLoad(u->aiUdpFlag) == 1 || force) && (u->sUdpSocket != INVALID_SOCKET)) {
+	if ((u->aiUdpFlag.load() == 1 || force) && (u->sUdpSocket != INVALID_SOCKET)) {
 #if defined(__LP64__)
 		STACKVAR(char, ebuffer, len+4+16);
 		char *buffer = reinterpret_cast<char *>(((reinterpret_cast<quint64>(ebuffer) + 8) & ~7) + 4);
@@ -1299,10 +1295,8 @@ void Server::newClient() {
 		// In Qt 5.4, QSsl::SecureProtocols is equivalent
 		// to "TLSv1.0 or later", which we require.
 		sock->setProtocol(QSsl::SecureProtocols);
-#elif QT_VERSION >= 0x050000
-		sock->setProtocol(QSsl::TlsV1_0);
 #else
-		sock->setProtocol(QSsl::TlsV1);
+		sock->setProtocol(QSsl::TlsV1_0);
 #endif
 		sock->startServerEncryption();
 	}
@@ -1327,14 +1321,9 @@ void Server::encrypted() {
 	QList<QSslCertificate> certs = uSource->peerCertificateChain();
 	if (!certs.isEmpty()) {
 		const QSslCertificate &cert = certs.last();
-#if QT_VERSION >= 0x050000
 		uSource->qslEmail = cert.subjectAlternativeNames().values(QSsl::EmailEntry);
-#else
-		uSource->qslEmail = cert.alternateSubjectNames().values(QSsl::EmailEntry);
-#endif
 		uSource->qsHash = cert.digest(QCryptographicHash::Sha1).toHex();
 		if (! uSource->qslEmail.isEmpty() && uSource->bVerified) {
-#if QT_VERSION >= 0x050000
 			QString subject;
 			QString issuer;
 
@@ -1347,10 +1336,7 @@ void Server::encrypted() {
 			if (! issuerList.isEmpty()) {
 				issuer = issuerList.first();
 			}
-#else
-			QString subject = cert.subjectInfo(QSslCertificate::CommonName);
-			QString issuer = certs.first().issuerInfo(QSslCertificate::CommonName);
-#endif
+
 			log(uSource, QString::fromUtf8("Strong certificate for %1 <%2> (signed by %3)").arg(subject).arg(uSource->qslEmail.join(", ")).arg(issuer));
 		}
 
@@ -1424,11 +1410,8 @@ void Server::sslError(const QList<QSslError> &errors) {
 		// See
 		// https://bugreports.qt.io/browse/QTBUG-53906
 		// https://github.com/mumble-voip/mumble/issues/2334
-#if QT_VERSION >= 0x050000
+
 		u->disconnectSocket();
-#else
-		u->disconnectSocket(true);
-#endif
 	}
 }
 
diff --git a/src/murmur/Server.h b/src/murmur/Server.h
index 79dd87b07..03e0b719b 100644
--- a/src/murmur/Server.h
+++ b/src/murmur/Server.h
@@ -65,11 +65,7 @@ class SslServer : public QTcpServer {
 		Q_DISABLE_COPY(SslServer)
 	protected:
 		QList<QSslSocket *> qlSockets;
-#if QT_VERSION >= 0x050000
 		void incomingConnection(qintptr) Q_DECL_OVERRIDE;
-#else
-		void incomingConnection(int) Q_DECL_OVERRIDE;
-#endif
 	public:
 		QSslSocket *nextPendingSSLConnection();
 		SslServer(QObject *parent = NULL);
diff --git a/src/murmur/Tray.h b/src/murmur/Tray.h
index 5ab77981b..c0d330571 100644
--- a/src/murmur/Tray.h
+++ b/src/murmur/Tray.h
@@ -8,12 +8,7 @@
 
 #include <QtCore/QStringList>
 #include <QtCore/QObject>
-
-#if QT_VERSION >= 0x050000
-# include <QtWidgets/QSystemTrayIcon>
-#else
-# include <QtGui/QSystemTrayIcon>
-#endif
+#include <QtWidgets/QSystemTrayIcon>
 
 class LogEmitter;
 class QAction;
diff --git a/src/murmur/main.cpp b/src/murmur/main.cpp
index 5572ea67c..ea6a99031 100644
--- a/src/murmur/main.cpp
+++ b/src/murmur/main.cpp
@@ -151,16 +151,10 @@ static void murmurMessageOutputQString(QtMsgType type, const QString &msg) {
 	}
 }
 
-#if QT_VERSION >= 0x050000
 static void murmurMessageOutputWithContext(QtMsgType type, const QMessageLogContext &ctx, const QString &msg) {
 	Q_UNUSED(ctx);
 	murmurMessageOutputQString(type, msg);
 }
-#else
-static void murmurMessageOutput(QtMsgType type, const char *msg) {
-	murmurMessageOutputQString(type, QString::fromUtf8(msg));
-}
-#endif
 
 #ifdef USE_ICE
 void IceParse(int &argc, char *argv[]);
@@ -220,9 +214,6 @@ int main(int argc, char **argv) {
 	MumbleSSL::initialize();
 
 	QTextCodec::setCodecForLocale(QTextCodec::codecForName("UTF-8"));
-#if QT_VERSION < 0x050000
-	QTextCodec::setCodecForCStrings(QTextCodec::codecForName("UTF-8"));
-#endif
 
 #ifdef Q_OS_WIN
 	// By default, windbus expects the path to dbus-daemon to be in PATH, and the path
@@ -252,11 +243,8 @@ int main(int argc, char **argv) {
 #endif
 
 	qsrand(QDateTime::currentDateTime().toTime_t());
-#if QT_VERSION >= 0x050000
+
 	qInstallMessageHandler(murmurMessageOutputWithContext);
-#else
-	qInstallMsgHandler(murmurMessageOutput);
-#endif
 
 #ifdef Q_OS_WIN
 	Tray tray(NULL, &le);
@@ -618,11 +606,7 @@ int main(int argc, char **argv) {
 
 	delete meta;
 
-#if QT_VERSION >= 0x050000
 	qInstallMessageHandler(NULL);
-#else
-	qInstallMsgHandler(NULL);
-#endif
 
 #ifdef Q_OS_UNIX
 	if (! Meta::mp.qsPid.isEmpty()) {
diff --git a/src/murmur/murmur_pch.h b/src/murmur/murmur_pch.h
index eb2405e94..c11c46269 100644
--- a/src/murmur/murmur_pch.h
+++ b/src/murmur/murmur_pch.h
@@ -32,19 +32,14 @@
 # include <QtDBus/QtDBus>
 #endif
 
-#include "QAtomicIntCompat.h"
-
 #ifdef Q_OS_WIN
 # include <QtGui/QtGui>
-# if QT_VERSION >= 0x050000
-#  include "Qt4Compat.h"
-#  include <QtWidgets/QtWidgets>
-# endif
 
 # include <ws2tcpip.h>
 # include <qos2.h>
 # include <shellapi.h>
 # include <delayimp.h>
+
 extern "C" {
 	void __cpuid(int a[4], int b);
 };
diff --git a/src/tests/TestSSLLocks/TestSSLLocks.cpp b/src/tests/TestSSLLocks/TestSSLLocks.cpp
index 7b9cc41a2..289138ea4 100644
--- a/src/tests/TestSSLLocks/TestSSLLocks.cpp
+++ b/src/tests/TestSSLLocks/TestSSLLocks.cpp
@@ -7,7 +7,6 @@
 #include <QtTest>
 
 #include "SSL.h"
-#include "QAtomicIntCompat.h"
 
 #include <openssl/rand.h>
 
@@ -30,7 +29,7 @@ public:
 
 	void run() {
 		unsigned char buf[64];
-		while (QAtomicIntLoad(*m_running) == 1) {
+		while (m_running->load() == 1) {
 			for (int i = 0; i < 1024; i++) {
 				if (m_seed) {
 					RAND_seed(buf, sizeof(buf));
diff --git a/src/tests/TestServerResolver/TestServerResolver.cpp b/src/tests/TestServerResolver/TestServerResolver.cpp
index e8c984509..ddafcdb11 100644
--- a/src/tests/TestServerResolver/TestServerResolver.cpp
+++ b/src/tests/TestServerResolver/TestServerResolver.cpp
@@ -13,13 +13,7 @@
 void signalSpyWait(QSignalSpy &spy) {
 	// We increase the timeout from 5s to 8s because travis builds could fail otherwise (slow network response).
 	const int signalTimeoutS = 8;
-#if QT_VERSION >= 0x050000
 	spy.wait(signalTimeoutS * 1000);
-#else
-	// Equivalent to QSignalSpy::wait() in Qt 5, except we do not return early on a spied on signal result.
-	QTestEventLoop loop;
-	loop.enterLoop(signalTimeoutS);
-#endif
 }
 
 class TestServerResolver : public QObject {
diff --git a/src/tests/TestServerResolver/TestServerResolver.pro b/src/tests/TestServerResolver/TestServerResolver.pro
index eab330173..e7d89aaf2 100644
--- a/src/tests/TestServerResolver/TestServerResolver.pro
+++ b/src/tests/TestServerResolver/TestServerResolver.pro
@@ -9,17 +9,7 @@ include(../../../qmake/qt.pri)
 QT *= network
 
 TARGET = TestServerResolver
-SOURCES *= TestServerResolver.cpp HostAddress.cpp ServerResolver_qt5.cpp ServerResolverRecord.cpp
+SOURCES *= TestServerResolver.cpp HostAddress.cpp ServerResolver.cpp ServerResolverRecord.cpp
 HEADERS *= HostAddress.h ServerResolver.h ServerResolverRecord.h
 
-isEqual(QT_MAJOR_VERSION, 4) {
-  CONFIG *= no-srv
-}
-
-CONFIG(no-srv) {
-  DEFINES += USE_NO_SRV
-  SOURCES -= ServerResolver_qt5.cpp
-  SOURCES *= ServerResolver_nosrv.cpp
-}
-
 win32:LIBS *= -lws2_32