How to find JIT bugs, the easy way

Go to Settings/Tools/Developer Tools/Jit Debug Tools. This controls which parts of the JIT are disabled.

Check boxes one by one, and try the game. Restart the game between each box you're checking (it's fine to load a save state).

Once the bug seems fixed, try unchecking all other checkboxes that seemed to have no effect.

Report the results! (Which box needed to be checked, and if unchecking some other box changed the outcome).

(If you feel advanced, you can bisect by halves instead - check half the boxes, see if that helps. then either check half of the checked boxes or the unchecked, depending on the results. Etc. You'll figure it out).