After 4.14 Better AI, enemies sometimes get "stuck" trying to approach you and simply stand still
Tried in webassembly version. Reproduce easily by finding the rat house and getting a pair of them to follow you. Start running away from them and you'll find they stop(even without you moving out of their vision range, this is not a chasing issue and for me at least still doesn't get fixed after the chapter where we add a chase timer), in this stopped state they seem to simply stand still forever or until someone rubs their bugged state by walking next to them or another NPC approaching to enter combat. While I can't reproduce this in your webassembly version, for me on my computer the performance drastically drops while enemies are in this bugged approach state.
Thanks! I'll see what I can find. I suspect that there's a bug in the target acquisition code, probably not updating the entity index properly (a perennial problem, I wish I'd done it a different way!).