I've issues to get my Zotac USB IR remote working on the RP4 with Libreelec 10.
Not all keys are recognized, for example Win Key, Teletext and those colored keys.
For me, it sounds like this problem: remote-woes-after-updating-to-9-2-1
There it was already marked as fixed in 9.2.4. But I still got those issues.
So I tried to follow the guide and was able to fix it but only partially. With those fixes I have laggs when I press keys. Every input is too slow or didn't get recognized correctly (eg. instead of one step down it scrolls ten times).
So i reverted those potential fix, enabled debbuging, rebooted and pressed some not working keys.
In the wiki i see some troublshooting tipps but the very first step isn't working here. With ir-keytable I get only "No devices found"