I had this problem for months, and this fixed it for me http://askubuntu.com/a/180505/53508
Unfortunately I had no success reverting settings to recapitulate the bug, so I cannot isolate it.
I had this problem for months, and this fixed it for me http:// askubuntu. com/a/180505/ 53508
Unfortunately I had no success reverting settings to recapitulate the bug, so I cannot isolate it.