I have successfully set up Tag Groups on my Discourse but in doing so ran into some weird issues which I mentioned here.
At the time I couldn’t figure out what was going on, but since playing with Tags and investigating I can successfully recreate the issue.
If you create a topic, add tags but then delete that topic before anyone else has used any of the tags, those tags become unusable site wide.
I can confirm this applies to any topic and any tag for any user.
This isn’t so much a problem if you lock down tag creation and create a topic in the Staff section to list your usable tags on, but it’s obviously a bug that will need fixing. The only solution I’ve found is to destroy those Tags using the Rails console. They then become selectable again.
