[2022] Can't log into rust+ with new steam mobile update

Reached out to Valve about this. For now it looks like if, after the Steam app automatically opens, you close the Steam app and switch back to Rust+ and click login again then it will open normally and let you in.

Not recommended: Alternatively if that isn't working you can try disabling "Open supported links" for the Steam app in your Android settings.

Valve have just pushed a fix for their app so there shouldn't be any more issues with signing into Rust+ anymore. Confirmed it's all good on my Android phone.

For iOS they mentioned that the fix would not need an app update but would need some caches to refresh on the phone in order for it to take effect. I'm not sure how long exactly it will take but hopefully better before tomorrow.