Mouse 4 and Mouse 5 hotkeys not working on Linux

Operating System Info

Other

Other OS

EndeavourOS

OBS Studio Version

31.0.3

OBS Studio Version (Other)

No response

OBS Studio Log URL

https://obsproject.com/logs/5eyC5DTOwZgn9xNv

OBS Studio Crash Log URL

No response

Expected Behavior

Add mouse 4 or mouse 5 as a hotkey for an action, such as push to talk. When I press mouse 4 or mouse 5, that action is activated.

Current Behavior

When using mouse 4 or mouse 5 as a hotkey, they don't work. Notably, I tried to use them as a hotkey for push to talk, and the push to talk doesn't activate every time I press it, and when it does activate, it only activates for a fraction of a second. When using as other hotkey actions it doesn't appear to work at all. Mouse 3 or other mouse buttons work fine, as well as all keyboard buttons.

https://github.com/user-attachments/assets/cee9df2b-1aae-4371-9d41-b08ab6ff5695

In the video I've set my middle mouse (mouse 3) and one side mouse button (mouse 4) to be able to toggle one of the window inputs. When the OBS window pops up in the top left, I'm using mouse 3, but as you see my mouse jiggle a little, I'm hitting mouse 4 and nothing is happening.

Steps to Reproduce

1. Add mouse 4 or mouse 5 as a hotkey to any action.
2. Attempt to use.
3. Watch as it doesn't work.

Anything else we should know?

Issue #8517 is basically the same issue, but it's marked as closed and the real issue is with using those mouse buttons as hotkeys in general, not just with push-to-talk. There seems to be no response to my request to re-open, so I'm making a new issue. Also related is issue #4843.

This bug becomes an issue on obs-studio 27.0.0, but works perfectly on obs-studio 26.1.2. Flatpack build has the issue as well.

Start by reproducing the issue on EndeavourOS with OBS Studio 31.0.3, using Mouse 4 and Mouse 5 for several hotkey actions and reviewing the linked OBS log. Compare the behavior with OBS Studio 26.1.2 and 27.0.0; done means both buttons reliably trigger assigned actions on Linux.