This one might be hard to reproduce because it just randomly works fine.. but I'd say 30%-50% of the time, when a player locks in a guess, the game master doesn't see it as "LOCKED IN" even though the timer after guess starts normally, the rest of the time it works completely fine.
Here's a video showing it first working normally, and then not detecting a locked in guess: https://youtu.be/QumYZ6DQnK8
I use this feature regularly and it was working totally fine a week ago, if that's of any help.