secondary monitor flickers after update

My secondary monitor flickers in Tumbleweed using Plasma desktop. This does not happen when using LXQT or any of the other desktop environments which I have tried.

here is part of the output from a “journal -b -1 -n 500” command

Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:26 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:26 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:26 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:26 linux-lcp7 plasmashell[2465]: org.kde.plasmaquick: Delayed preload of  "Application Menu" after 0.348 seconds
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:26 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:26 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:26 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:27 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:27 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 plasmashell[2465]: trying to show an empty dialog
Aug 29 15:54:27 linux-lcp7 plasmashell[2465]: org.kde.plasmaquick: Applet "Application Menu" loaded after 124 msec
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:27 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 plasmashell[2465]: file:///usr/share/plasma/plasmoids/org.kde.plasma.notifications/contents/ui/NotificationDelegate.qml:119:22: Unable to assign [undefined] to QQmlListModel*
Aug 29 15:54:27 linux-lcp7 plasmashell[2465]: file:///usr/share/plasma/plasmoids/org.kde.plasma.notifications/contents/ui/NotificationDelegate.qml:113: ReferenceError: appIcon is not defined
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:27 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680
Aug 29 15:54:27 linux-lcp7 kernel: [drm:radeon_cs_ioctl [radeon]] *ERROR* Invalid command stream !
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:481 cb[0] bo too small (layer size 9830400, offset 0, max layer 1, bo size 4096, slice 38399)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_cs_track_validate_cb:485 problematic surf: (1920 1280) (4 4 1 1 2 1024 2)
Aug 29 15:54:27 linux-lcp7 kernel: radeon 0000:02:00.0: evergreen_packet3_check:1948 invalid cmd stream 680

any assistance would be greatly appreciated, thanks

interesting note, if I logout and then login to the Gnome with Xorg desktop, then both monitors work correctly.

if I then logout again and login back in with Plasma (not with the Wayland version), then the second monitor works correctly and is not flickering.

If xf86-video-ati is installed, try removing it, to switch graphical environment from radeon to modesetting.