This may not be the same softlock but I had a viewer who said "i was playing against 89, and im guessing what happened is that 89 stole my X and played it as a 0 and that broke the game" and reports the game being unplayable even after a refresh. Did not try this myself but thought maybe it was worth relaying
sorry, the person who sent the bug report clarified "saw your bug report. for the record, ai played 0 against me, it softlocked the game, but was playable again after a refresh. something in M1 (specifically, me playing the 27 with a full hand) permanently bricked the game for me, even after a refresh" (so yeah I knew the 0 softlock is intentional but wasn't sure if that's what the player meant)
the person also says it's bricked webgl totally so it may be a coincidence :/ sorry