Created attachment 6688
Force NorthWest gravity for application windows.
LibreOffice incorrectly sets its top level windows win_gravity field to StaticGravity. Resizing these windows to the left or upwards results in a corrupted application with the application window moved within the parent by the parent window resize.
Metacity forces window gravity for all application windows to NorthWest, masking this application bug. xfwm4 should do the same.
A bug has been filed against LibreOffice as well.
Sure, seems safe to do that. Thanks for root causing the issue and the patch!
Pushed to both xfce-4.12 and master
*** Bug 12361 has been marked as a duplicate of this bug. ***