Just migrated 4.1 to 4.2, SSIL is suddenly poorly performing?

[longplay_games]

Godot Version

4.2.2.stable.official

Question

Upgraded project from 4.1.1 to 4.2.2 yesterday. Ran mass conversion of all scenes, saved, restarted.
Now when running some scenes framerate has dropped from stable 200 FPS to < 10 FPS and it appears that SSIL is the vast majority of the cause:

Is there a known change I should adjust for there? I can just blindly flail around adjusting settings until it runs like it ran on 4.1.1, but that seems unproductive.

This is a screenshot from the backup I took prior to upgrading, running under 4.1.1 (just because everyone claims it “worked fine yesterday”), so this is one I checked right this moment on the older version:

So you can see with no changes to the project other than the upgrade/re-save, SSIL jumped from 0.56ms per frame to 17.59 ms. Resolve depth jumped from 0.11 to 2.84 as well.

[longplay_games]

I guess it was some sort of issue going direct from 4.1.1, I tried going to 4.1.4 and THEN to 4.2.2 and… 200 FPS. Wild.