Hi! I checked today and it seems to still be working for me, both on PC and mobile. This add-on blocks the posts after you scroll for some time and reach "You're all caught up". Before that, it's only posts about people you follow, and after "You're all caught up" you'll only see suggested posts by IG algorithm. That second section is the one this add-on is blocking, you should be unable to continue scrolling past "You're all caught up".
Was your expectation that this would block all posts under the stories section? Let me know, I'd be happy to make a different add-on for that scenario :)

Feel free to edit your review to answer