Hello @spuxx1701, on Steam's side of this issue, it looks like this issue is currently being tracked at #8604. Closing in favor of the older issue report.
Ah, #8604 has slipped past my attention. I would have preferred an issue with more information and one that's less specific, but alright.
Man what a dream, this would be terribly nice...
Your system information
Please describe your issue in as much detail as possible:
Current behavior: When connecting an XInput controller (an 8bitDo Ultimate Pro in my case) to your machine and running steam with Steam Input and a Desktop layout for said controller enabled, the controller input, particularly mouse emulation, will not work when using Wayland. It will work as expected when using X11.
Expected behavior: Steam Input and its desktop mode should work when using Wayland.
I am aware that this issue has been raised in various ways in multiple places, e.g.
However, @kisak-valve has been repeatedly closing these issues, pointing at https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/431, a merge request over at Wayland. If you read into that merge request, you will quickly notice that it is very unlikely to ever be merged. I quote:
This is not not something that will or should be solved in Wayland. Instead, Valve should migrate key functionalities of their client to support Wayland, which is steadily becoming the new standard and replacing X11. As far as I understand, this issue also blocks e.g. Steam Deck to utilize Wayland in desktop mode (although it is likely not the only blocker) since it would render the Steam Deck's controls unusable in desktop mode. Please do not simply close this issue. It remains a problem and it will not be fixed by Wayland. For many users, Wayland has become the preferrable choice over X11 due to that one's problems with e.g. screen tearing. Many of us rely on companies like Valve to improve their support of Wayland.
Steps for reproducing this issue:
I will try to maintain a list of related links and places this issue has also been documented. As of know, documentation is really fragmented and I'm hoping that others running into the same problem will find this issue and gain a better understanding of it.