MC 1.19.2
QSL 4.0.0-beta.30
ModernFix 3.5.0

The game simply crashes on startup, unless I set the config value mixin.perf.faster_texture_loading=false. Everything else seems to work perfectly fine. Let me know, if this needs to be reported to QSL, instead, especially since you didn't explicitly tag Quilt as supported.

Edit: I also can't find this feature on the list.

Edit 2: This may actually be because QSL might be doing the same thing as this mixin.

Logs: https://gist.github.com/SplendidAlakey/83fb666055e33fe26cee4046500d49c8

Will be fixed in next release/when dev build finishes compiling.