Minor edit

Dockerfile

@@ -478,6 +478,7 @@ ENV KDE_SESSION_VERSION=5
 ENV KDE_APPLICATIONS_AS_SCOPE=1
 ENV KWIN_COMPOSE=N
 ENV KWIN_EFFECTS_FORCE_ANIMATIONS=0
+ENV KWIN_EXPLICIT_SYNC=0
 ENV KWIN_X11_NO_SYNC_TO_VBLANK=1
 # Use sudoedit to change protected files instead of using sudo on kwrite
 ENV SUDO_EDITOR=kwrite