@dunlix (and others)
Thanks, the disable plugins suggestion worked. Apparently it was the "sanitize html" plugging that was causing the problem.
Not even sure why we had that still installed.
Thanks all for the troubleshooting help!
I have kinda unusual case: multiple topics can belong to one or more categories, so I decided to use combination of tags and categories - because by default in NodeBB topic can belong only to one category (which can have at most one parent).
Example: Let's imagine a topic which belongs to following categories: technical support, nodebb plugin development and nodebb development. Main or primary category would be technical support, and tags would be technical-support, nodebb-plugin-development, nodebb-development.
How to display that topic also in categories nodebb plugin development and nodebb development?
I found following plugin and was wondering if it was possible to display topics category with tag with same name:
https://github.com/cwis-public/nodebb-plugin-merge-subtopics
@metalkramp it sounds like it may be easier for you to only use tags in this case, and use a custom plugin to display certain tags as if they are categories.