The bug

This bug happens in two different circumstances. Nonetheless, it appears to be the same bug, and I didn't want to duplicate my own bug. If you believe these are different issues, let me know and I can make a new one.

1. If you increase your FOV, the chunks that were previously out of your view do not come into view until you move your player's head slightly. (This is a very old issue which was once fixed but has returned (this part was in 1.16.5); I don't know the original ticket number.)
2. When the world first loads, chunks, usually 4 or more away, occasionally do not render until the player shifts their head slightly. (This is a new issue which did not happen previously, since one of the 1.17 snapshots.)

Steps to reproduce

1. Stand on a platform ~15 blocks up in the sky. (This is just so you can see the chunks better.)
2. Set your FOV to 30
3. Look around a bit
4. Crank your FOV all the way up, but don't move your mouse once your game is unpaused.

-->  Notice that the chunks do not come into view properly.