Unfocusing window causes certain games to need to desync and need to entirely redraw or freeze

Mirrored from https://github.com/Supreeeme/xwayland-satellite/issues/201:

I've been testing out in Niri. Upon the launch of World of Warcraft: Mists of Pandaria Classic's prepatch, it seems to desync when not focused. If I leave it like that for a few seconds, it'll need to redraw the frame entirely.

If left there for more than 10-15 seconds, it will entirely freeze, and be unable to recover. It is worth noting this behaviour does NOT happen on World of Warcraft Classic Anniversary under the same circumstances. It also does not happen when force-unsetting DISPLAY to run using the native Wayland Wine Driver, though Battle.net itself becomes nearly unusable when used like that, so running on xwayland is still ideal. It also does NOT happen under other compositors - even when running under xwayland-satellite.

Steps to Reproduce:

Redrawing Behaviour:

1. Boot up World of Warcraft: Mists of Pandaria Classic
2. At any point, unfocus the game (easier to see in-game though)
3. Wait a few seconds
4. Refocus the game

Freezing Behavior

1. Boot up World of Warcraft: Mists of Pandaria Classic
2. At any point, unfocus the game (easier to see in-game though)
3. Wait 10-15+ seconds
4. Refocus the game

Niri Config attached in a gist: https://gist.github.com/Seralyne/faa07febc5eb2fa661d4bcaf372e196e

While this is an issue with a X11 app, it is something I can only reproduce in Niri - even running under xwayland-satellite on other compositors. It does not happen when running Wine under Wayland on Niri, although it does make Battle.net nigh-unusable, and I can't reliably open games when running under those conditions.

System Information

• niri version: niri 25.05.1 (8ba57fc)

• Distro: Arch Linux

• GPU: Nvidia RTX 3070 Ti

• CPU: AMD Ryzen 5 3600X