if you only have one devlice and Steam mobile and Steam chat is on same device and Steam Guard is enabled, then its actuelly totally impossible to login, due the very absurd short timer to remember the code (which im newer can) and insert it between both apps.

The problem is impossible for me to do that as there is no copy & paste feature the code. Im have 10 secs or such. complete useless.

So im can currectly no longer uses Steam Chat at all.