The flag was preventing Krusader from exiting if Krusader::queryClose() was
called but the exit was later cancelled (e.g. by a file save dialog of
KrViewer).
And the destructor Krusader::~Krusader() is not called on a SIGTERM signal
anyways.
FIXED: [ 409473 ] Computer shutdown gets cancelled
BUG: 409473
AND
Fix main window beeing closed to tray instead of exit on session logout