Fullscreen windows are not raised correctly after KWin 6.7.5 update

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1

Product: KWin

Component: Wayland / Window Management

Version: 6.7.5

After updating Plasma/KWin from 6.7.4 to 6.7.5 on CachyOS, switching between fullscreen application windows stopped working correctly on Wayland.

The affected application is EVE Online running through Steam/Proton, but the issue appears to be related to KWin window activation/stacking rather than Proton itself.

I tested both Proton 11 and Proton Experimental and the behavior is identical.

Two fullscreen EVE windows are recognized correctly by KWin. Both report:

fullscreen: true
normalWindow: true
skipSwitcher: false
skipTaskbar: false
type: 0
resourceClass: steam_app_8500

They have different PIDs, captions and UUIDs.

Steps to reproduce:

  1. Start EVE Online through Steam/Proton on Plasma Wayland.
  2. Open one fullscreen/fixed-window EVE client.
  3. Open a second EVE client, or even just the EVE launcher.
  4. Use Alt+Tab to select the other EVE window.

Expected result:

The selected window should immediately become visible and be raised above the current fullscreen window.

Actual result:

The selected EVE window appears to become activated internally, but remains visually behind the current fullscreen window.

If I then Alt+Tab to Firefox or a terminal, the previously selected EVE window suddenly appears underneath the newly activated Firefox/terminal window.

Example:

EVE client A visible
Alt+Tab → EVE client B
Nothing visible changes
Alt+Tab → Firefox
Firefox appears, and EVE client B is now directly behind it

The same behavior occurs with a custom KWin script using workspace.activateWindow(window, true), so this does not appear to be limited to the Alt+Tab UI.

Switching EVE to normal windowed mode is not a usable workaround because the client freezes when changing to that mode.

This started after the recent Plasma/KWin updates.

Current versions:

kwin 6.7.5-1.1
plasma-workspace 6.7.5-1.1
kwayland 6.7.5-1.1
libplasma 6.7.5-1.1
kwindowsystem 6.30.0-1.1
qt6-base 6.11.2-3.1
xorg-xwayland 24.1.13-1.1

Relevant upgrade history:

2026-09-09:
kwin 6.7.4-7.1 → 6.7.5-1
kwayland 6.7.4-1.1 → 6.7.5-1
plasma-workspace 6.7.4-3.1 → 6.7.5-1

2026-09-10:
kwin 6.7.5-1 → 6.7.5-1.1
kwayland 6.7.5-1 → 6.7.5-1.1
plasma-workspace 6.7.5-1 → 6.7.5-1.1
kwindowsystem 6.29.0-1.1 → 6.30.0-1.1

System:

CachyOS
KDE Plasma Wayland
NVIDIA GeForce RTX 3090
NVIDIA driver 610.57.04

There are no NVIDIA Xid errors and no OOM events in the journal.

2

that sounds like a kwin stacking/activation regression on wayland more than proton, especially since workspace.activateWindow with force true does the same thing.

worth filing a kwin bug with your window properties dump and the 6.7.4 to 6.7.5 upgrade list. for a temporary workaround people usually either:

- pin one client to a different virtual desktop, or

- downgrade kwin/plasma-workspace back to 6.7.4 packages if cachy still has them in cache

if you can also test two normal (non-steam) fullscreen apps doing the same alt-tab fail, that makes the kwin report cleaner.

3

Can agree. Switching back to kwin-6.7.4 fixed the issue.

4

Unable to rollback to kwin-6.7.4 but I am having a related issue where input is being partially passed to full screen games, leading to WASD movement becomming unresponsive and the mouse pointer not being captured

In No Man’s Sky, for example; I have to pull down the krunner search bar, start typing, and mash ESC to regain full control of the game

5

For me this issue was also fixed by changing (lowering) the “Focus stealing prevention” from high to medium under Settings->Window Management->Window Behaviour->Focus.