Multiple rendering issues in 1.21.11: slimes invisible (particles only) + first-person hand stretched/distorted

After updating to 1.21.11 I’m getting two visual bugs. Slimes appear invisible and only their green hit particles show even though they still move and make sounds. My first-person hand also glitches and turns into a long black stretched object that sticks out in front of the camera. Third person looks normal.

Steps:

1. Start a world in 1.21.11

2. Spawn or find a slime

3. Switch between first and third person a few times

4. Both glitches can show up randomly

Expected:
Slimes look normal and the first-person hand looks normal.

Observed:
Slimes are invisible except for particles. The first-person hand sometimes becomes stretched and distorted.

Notes:
No mods. Default settings. Restarting the game fixes it for a bit.