Severe glitches in cinnamon/gnome3 affecting small rectangular areas (menus, dialogs)

Submitted by sdi..@..ail.ru

Assigned to Default DRI bug account

Description

Created attachment 145618
Unreadable file copy dialog (cinnamon filemanager)

I witness a gradually developing regression that results in increasingly nasty graphical glitches in the cinnamon and gnome3 desktop environments. It has reached the point when it becomes impossible to see, what GUI button or menu item you are clicking, which makes the whole desktop unusable.

The bug affects relatively small rectangular areas containing individual GUI elements. See attached screenshots.

Dialogs that are close to a square in shape are less likely to be garbled, Wider dialogs look worse.
The bug disappears immediately if I run a different desktop compositor using commands like "compiz --replace".

Affected DE-s:
- Cinnamon (strong)
- Gnome3 (less)

Not affected DEs|WMs:
- mate
- muffin (cinnamon wm run independently of its DE)
- compiz

KDE not tested by me.

My hardware and kernel:
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Turks XT [Radeon HD 6670/7670]
Linux kernel 4.19.72, radeon.ko driver

The regression started with small systray icons, than it spread to hint and notification boxes. Since about a week ago (my latest update) it affects menus and dialog boxes as well. The same dialogs that become ureadable in cinnamon may look normal in gnome3 (without normal wm titlebar).

**Attachment 145618**, "Unreadable file copy dialog (cinnamon filemanager)":