https://gist.github.com/chewey32/04bf8647a421fa37eaedd44474d57f10

1. If this setting is enabled with a compatible resource pack (I've tested both Reimagined and Fresh Animations w/ extensions) prior to loading Minecraft with Forgery, the game will freeze indefinitely on startup.
2. If this setting is disabled on startup, a resource pack utilizing random entities is loaded, and, after, the setting enabled alongside Forgery, the game will freeze and eventually crash (see crash log).
3. If Minecraft is booted with this setting turned on and there is no resource pack that utilizes the feature, Forgery works as expected, but the game will freeze indefinitely if one of these resource packs is loaded.

This issue seems to be replicable across every version of 1.20.1 Forge, OptiFine, and Forgery, and persists despite all options being disabled in the Forgery config.