On my laptop, this has caused it to not crash, but it has been on the loading screen for watching this match I picked arbitrarily for several minutes now.
Edit: it loaded
I've tried both the on-screen keyboard and a remote computer with a physical keyboard connected via Remote Play, both with the Steam Deck in game mode and with the Steam Deck in desktop mode. No numbers appear in the match ID box (Watch->Search By Match ID) when I type numbers.