Docs plugin does not filter tags after selecting category


Desktop, macOS, Ventura 13.4, Safari 16.5

Available tags are not filtered by selected category in docs plugin. In the inverse, available categories are filtered out if the selected tag is not used in the category.

Selecting a tag not used in the selected category results in the docs UI being replaced by a message with no obvious way of recovering. This could be addressed with a link to /docs, effectively a way of resetting any selection.

Reproducible steps:

  1. Go to /docs
  2. Select the blog category (only the getting-started tag is used here at time of writing)
  3. Select the how-to tag (any tag that is not used in the blog category)

Expected results:
After step 2, I expect to only see the getting-started tag available to select, i.e. only the tags used in the selected category.

Step 3 should not be possible but after step 3, I expect to be able to recover without knowing to press back or modify the query string in the address.

Actual results:
After step 2, all tags are available to be selected, including those not used in the category.

After step 3, the No Docs topics yet message replaces most of the docs UI with no obvious way of getting it back.

There are a number of ways to escape this state such as going back in the browser or using the search, then removing the tag selection but these may be non-obvious to less technical users. The selection also persists through Discourse navigation until a browser refresh somewhere away from /docs.