Greasy Fork

While this does work to remove the sponsored posts within the feed for the most part, it also removes the description of posts in the Marketplace.

Nice catch, the version 1.8.2 disables this script in the marketplace.

Updated to 1.8.2 and retried, still appears to be blanking out the description, but only when the post is in its 'fullscreen' mode.
Not exactly sure how to explain it. Happens when initially clicking on a marketplace post, then the post defaults into a blows up size and takes over the entire browser space. The description/sidebar appears for a moment, then disappears.
If I refresh/F5, the post goes into a smaller view and the description stays

Updated to 1.8.2 and retried, still appears to be blanking out the description, but only when the post is in its 'fullscreen' mode [...]

I'm not sure how to reproduce this. When I click on a post, I get a fullscreen post where my script is not running. In your case, is the url like "www.facebook.com/marketplace/item/..." ? Thx!

Yep, the URL does appear like that. It maybe a conflict with Clean My Feeds, which was recently updated to fix their issue of Sponsor blocking. I had it disabled when testing this script though who knows if I have another script/addon that was conflicting with it