See File page and pinned post for description of version 3. No AddOn file required. If NPCs/animals use Thormin's detection dialogue there is a fix in the miscellaneous section.
Main difference between 3.1 and 3.0 is to make compatible with BS: Bruma. There are other minor fixes but if you're running on 3.0 without Bruma there's no major need to update. The NPC detection fix is included in 3.1.
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