Looking pretty good, just for clarification: This only shows completions for tag combinations still possible with what comes before, correct?

Other than that, the console.log on line 730 can be removed or commented out, I just forgot to take that out after I finished testing the original implementation. It's a bit too spammy for normal use. The rest of the logs probably as well if you don't need them further.

I don't have time to try it out myself right now, but I will trust you that it doesn't break unrelated functionality.

OK, had to rewrite it a bit because the initial implementation was only optimised for a single umi tag in a prompt. Moreover, the filtering logic depends on which tag the cursor is focused at and this further complicated things. I feel it's pretty solid now. Please double-check me before merging if you find a minute because I'm far past my bedtime.

Functionality wise, it seems good to me, normal completion also doesn't seem impacted, so all good to go.

The only issue I noticed is that editing negative tags sometimes doesn't show completion if later tags have already restricted the tags further. E.g., <[female][fullbody][--western][chinese]> will not show completion when going back to edit --western, since western has already been removed from the candidates by the later chinese. Technically it should still show since negative could be anything not explicitly required by the chinese, but that's hard to do since retroactive changes to front tags would obviously impact later ones. Since this format is especially supposed to work with sequential completion, I don't think it's a big issue, so I'll still merge it now. Maybe we can think of something later, but that's not a priority.

Other than that there's only one console.log left that fills the console with the matches object, but I'll remove that myself after merging. There's still another one left in unrelated code, so I'll just do them both together.

Yeah, retroactive editing is a bit clunky but it shouldn't be a big issue (I hope). We'll see what feedback people will leave.

Thanks for merging it :).