Wanted to also echo some bugs with prone mechanics. My warlock got knocked prone on a couple occasions.

1. The first time, she stood up, and the UI disappeared, but only for her. I was able to press spacebar to progress to the next turn, and my other characters still had a visible UI. I reloaded, so not sure if finishing combat would have reset the UI.
- (Also, is there a command to refresh the UI?)

2. The second time my warlock fell prone, when she stood up, she couldn't complete any actions/bonus actions/abilities/etc. I'd click Jump and select a destination, and she'd pause for a few seconds, the sound would play, and she'd still be standing there with no movement or bonus action depleted. Same with Eldritch Blast -- she'd pause, sound would play, and then nothing would happen, and she'd still have her action available. She was able to move, though. The issue persisted to her next turn.