The problem solved for me today, upgraded my GFX card (old nvidia with usage of nvidia driver version 173). The new card supports the latest drivers by ubuntu (version 185) and since this update the problem has gone.
So in my case, it is/was nvidia driver related.
The problem solved for me today, upgraded my GFX card (old nvidia with usage of nvidia driver version 173).
The new card supports the latest drivers by ubuntu (version 185) and since this update the problem has gone.
So in my case, it is/was nvidia driver related.