diff --git a/utils.cpp b/utils.cpp
--- a/utils.cpp
+++ b/utils.cpp
@@ -84,7 +84,13 @@
     // NOTE: QX11Info::getTimestamp does not yet search the event queue as the old
     // solution did. This means there might be regressions currently. See the
     // documentation above on how it should be done properly.
-    kwinApp()->setX11Time(QX11Info::getTimestamp(), Application::TimestampUpdate::Always);
+    const auto timestamp = QX11Info::getTimestamp();
+    if (timestamp == 0) {
+        // 0 indicates an error when trying to get the timestamp. Don't update to that
+        // TODO: implement getTimestamp on Wayland
+        return;
+    }
+    kwinApp()->setX11Time(timestamp, Application::TimestampUpdate::Always);
 }
 
 static int server_grab_count = 0;