It’s true there are a lot of better alternatives to jami when it comes to privacy/security: Here’s a good comparison table:

https://www.messenger-matrix.de/messenger-matrix-en.html

I saw your conversation on the simracing-channel and there seems to be some progress. I just realized from my notes that my handbrake does not cause any issues under linux even if it looks the same as yours. (They must have implemented the software differently on mine). I had to make some adjustments for the pedals and H-shifter but not the handbrake and just misremembered, sorry. Protopedal is what I used to get around the bug in proton, though. I think proton does not recognize a usb device as controller, if it does not have a certain number of buttons and/or axes.

I am glad to hear you got it to work! I think I took notes on how I got it to work. But I remember having also added a similar rule as you did at some point. I may be able to find my notes tomorrow.

I am pretty sure you need to configure more (fake) buttons for the handbrake, I had the same problem. Otherwise it does not get recognized as a gaming device.

I can look up later how I solved this or you can ask the simracing linux community, which helped me with a couple of similar pronlems before:

A place for all the niche of niche gamers to discuss and join other simracers!
Join the Simracing space here https://matrix.to/#/#simracing:matrix.org