diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
index f542907c669..48d6d0633b6 100644
--- a/src/tests/CMakeLists.txt
+++ b/src/tests/CMakeLists.txt
@@ -20,6 +20,7 @@ if(client)
 		# For some reason Qt segfaults when executing this test on FreeBSD without a display (even when using the offscreen plugin)
 		use_test("TestSettingsJSONSerialization")
 	endif()
+	use_test("OverlayTest")
 endif()
 
 if(server)
diff --git a/src/tests/OverlayTest/CMakeLists.txt b/src/tests/OverlayTest/CMakeLists.txt
new file mode 100644
index 00000000000..c47fa6a2c57
--- /dev/null
+++ b/src/tests/OverlayTest/CMakeLists.txt
@@ -0,0 +1,18 @@
+# Copyright 2020-2022 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>.
+
+add_executable(OverlayTest OverlayTest.cpp)
+
+set_target_properties(OverlayTest PROPERTIES AUTOMOC ON)
+
+find_pkg(Qt5 COMPONENTS Gui Widgets REQUIRED)
+
+target_link_libraries(OverlayTest PRIVATE mumble_client_object_lib)
+target_link_libraries(OverlayTest PRIVATE shared Qt5::Test Qt5::Widgets)
+
+add_test(NAME OverlayTest COMMAND $<TARGET_FILE:OverlayTest>)
+
+# OverlayTest is disabled because it can only be tested by humans checking that the application is correctly displaying the overlay
+set_tests_properties(OverlayTest PROPERTIES DISABLED TRUE)
diff --git a/src/tests/OverlayTest/OverlayTest.cpp b/src/tests/OverlayTest/OverlayTest.cpp
index 8d8e8e4a732..012c8c249c7 100644
--- a/src/tests/OverlayTest/OverlayTest.cpp
+++ b/src/tests/OverlayTest/OverlayTest.cpp
@@ -21,7 +21,10 @@
 #include <QtGui>
 #include <QtNetwork>
 
-#include <ctime>
+#include <QWidget>
+#include <QMainWindow>
+#include <QApplication>
+
 
 class OverlayWidget : public QWidget {
 	Q_OBJECT
@@ -33,7 +36,7 @@ class OverlayWidget : public QWidget {
 	SharedMemory2 *smMem;
 	QTimer *qtTimer;
 	QRect qrActive;
-	QTime qtWall;
+	QElapsedTimer qtWall;
 
 	unsigned int iFrameCount;
 	int iLastFpsUpdate;
@@ -185,7 +188,6 @@ void OverlayWidget::error(QLocalSocket::LocalSocketError) {
 void OverlayWidget::update() {
 	++iFrameCount;
 
-	clock_t t     = clock();
 	float elapsed = static_cast< float >(qtWall.elapsed() - iLastFpsUpdate) / 1000.0f;
 
 	if (elapsed > OVERLAY_FPS_INTERVAL) {
@@ -216,12 +218,12 @@ void OverlayWidget::readyRead() {
 		int ready = qlsSocket->bytesAvailable();
 
 		if (om.omh.iLength == -1) {
-			if (ready < sizeof(OverlayMsgHeader))
+			if ((size_t)ready < sizeof(OverlayMsgHeader))
 				break;
 			else {
 				qlsSocket->read(reinterpret_cast< char * >(om.headerbuffer), sizeof(OverlayMsgHeader));
 				if ((om.omh.uiMagic != OVERLAY_MAGIC_NUMBER) || (om.omh.iLength < 0)
-					|| (om.omh.iLength > sizeof(OverlayMsgShmem))) {
+					|| ((size_t)om.omh.iLength > sizeof(OverlayMsgShmem))) {
 					detach();
 					return;
 				}
@@ -264,11 +266,12 @@ void OverlayWidget::readyRead() {
 					if (!smMem)
 						break;
 
-					if (((omb->x + omb->w) > img.width()) || ((omb->y + omb->h) > img.height()))
+					if (((omb->x + omb->w) > (unsigned int)img.width())
+						|| ((omb->y + omb->h) > (unsigned int)img.height()))
 						break;
 
 
-					for (int y = 0; y < omb->h; ++y) {
+					for (unsigned int y = 0; y < omb->h; ++y) {
 						unsigned char *src =
 							reinterpret_cast< unsigned char * >(smMem->data()) + 4 * (width() * (y + omb->y) + omb->x);
 						unsigned char *dst = img.scanLine(y + omb->y) + omb->x * 4;