Prevent dragging sidebar folders: Closes #4701
Prevent dragging sidebar folders: Closes #4701

martinra/geary,MohamedIM/geary-unofficial,tshikaboom/geary,mjog/geary,githubnemo/geary,mjog/geary,mpdeimos/geary,jimbonator/geary,robol/geary,jimbonator/geary,jimbonator/geary,robol/geary,rschroll/geary,kpiwko/geary,emersion/geary,glebihan/geary,abn/geary,aatishnn/geary,glebihan/geary,AtticHacker/geary,martinra/geary,AtticHacker/geary,tshikaboom/geary,AtticHacker/geary,geekvigilante/geary,aatishnn/geary,githubnemo/geary,aatishnn/geary,emersion/geary,mjog/geary,robol/geary,kyoushuu/geary,kyoushuu/geary,rschroll/geary,glebihan/geary,emersion/geary,githubnemo/geary,martinra/geary,tshikaboom/geary