Without this patch, plasma-workspace fails to compile for me with the following error:
In file included from /home/nate/kde/build/plasma-workspace/runners/windows/krunner_windows_autogen/EWIEGA46WW/moc_windowsrunner.cpp:10, from /home/nate/kde/build/plasma-workspace/runners/windows/krunner_windows_autogen/mocs_compilation.cpp:2: /home/nate/kde/build/plasma-workspace/runners/windows/krunner_windows_autogen/EWIEGA46WW/../../../../../../src/plasma-workspace/runners/windows/windowsrunner.h:61:9: error: ‘QMutex’ does not name a type 61 | QMutex m_mutex; | ^~~~~~