How to Check Whether a Mod's Mixins Are Actually Loading

Sometimes a mod seems installed but its changes do not apply. MixinTrace helps you confirm whether its mixins were applied at all, by surfacing mixin information in crash output and logs.

Force a crash to generate output

MixinTrace only adds its detail when a crash report is produced, so you need a crash to inspect. If the game is not crashing on its own, trigger a controlled crash (for example by deliberately causing a known error) so a report is written. Open the newest file in crash-reports.

Search for the mod's mixins

In the MixinTrace section, search for the mod's identifier — the same string that appears in its configuration name and usually in its jar filename. If you find entries, the mod's mixins loaded and were applied to their target classes. If the mod is installed but no mixins appear under its identifier, its mixins either failed to apply or target classes that were not involved in this particular crash.

Interpret the result

Absence in one crash report is not proof of failure — only classes in the crash path are listed. To be sure, cause a crash that involves the class the mod is supposed to patch. If its mixin still never appears, check for a load error earlier in the log, which usually explains why the injection was skipped.