Fix #5913, ISE: Fatal Exception thrown on Scheduler.Worker thread
Fix #5913, ISE: Fatal Exception thrown on Scheduler.Worker thread

- Guard updating of popup ui against the opup being dismissed already

superspindel/cgeo,matej116/cgeo,cgeo/cgeo,mucek4/cgeo,S-Bartfast/cgeo,cgeo/cgeo,tobiasge/cgeo,cgeo/cgeo,tobiasge/cgeo,mucek4/cgeo,auricgoldfinger/cgeo,rsudev/c-geo-opensource,pstorch/cgeo,S-Bartfast/cgeo,kumy/cgeo,pstorch/cgeo,Bananeweizen/cgeo,rsudev/c-geo-opensource,superspindel/cgeo,mucek4/cgeo,cgeo/cgeo,matej116/cgeo,pstorch/cgeo,S-Bartfast/cgeo,matej116/cgeo,Bananeweizen/cgeo,kumy/cgeo,rsudev/c-geo-opensource,tobiasge/cgeo,superspindel/cgeo,auricgoldfinger/cgeo,Bananeweizen/cgeo,auricgoldfinger/cgeo,kumy/cgeo