We provide articles base from commons ticket's question.  So before open new ticket, you can explore and read the articles. If your problem already answer on the articles, it will make faster to resolve your problem.


My Sidebar disappear from dashboard

Try to deactivate GPP SLideshow. Sometime conflict caused by environment on your system. That plugin only for slide post gallery (you can use jetpack then.) 

If the problem still show up, try to deactivate the others plugin till you find which plugin caused the problem.