Not sure how to reproduce this, but my tag pane is showing an empty hash tag (i.e. just #):

As you can see, it thinks I have 9 documents with this hashtag…
Compounding this, clicking on a hashtag in that list to see its instances just performs a naive search of the whole vault vs the hashtag text, which returns many many more than 9 hits for this hashtag because # is used in markdown headings, so I have lots of instances of #, ##, ###, etc. in my vault.
No idea where those 9 are supposed to be…!
Environment
- Operating system: MacOS 10.14.6