UPDATE: Figured it out. I'd selected the "Whole Word" option, and once I unchecked it the filter worked perfectly.

Thank you all for the suggestions.

Is there a way to filter out posts with specific #hashtags ???

@dangillmor there's filters for generic strings, and # is just another character you can put in one.
I'm not sure there's a shorter way 🤔
@viq @dangillmor I think this is pretty much the way do it. I have three separate filters, but each has multiple hashtags in it because I get very tired of seeing categories of stuff in my feed. And even more tired of it if I decide to peruse the Trending feed.
@roadskater @viq It's not working for me for some reason. I added a specific hashtag to a filter and posts using that hashtag are still showing up.
@dangillmor Did you clear your browser's cache?
@femme_mal @dangillmor Also check your filter to see what contexts it's being applied to. None of them are checked by default.
@roadskater @femme_mal "Whole Word" is checked by default. It worked once I unchecked it.