• on the mobile app, comments have links to search for fairly random words within them in YouTube search for no discernable reason
• the comment box on mobile shows a preview of a comment, but when clicking on the preview it just goes to the top of the comments and the comment you clicked on is now lost
• YouTube search works terribly and is less than 1/3 actual results
• searching by upload date only shows around a dozen new videos before it completely stops working
• searching watch history for terms in video titles almost never works, even if there are lots of videos with said title
• ambient mode distracts from the video itself and looks pretty bad on Firefox
• the tracking code when sharing links
• how some videos have different caption formatting and there is no central way to turn it off for good
• YouTube thumbnails are big now
• YouTube recommending me a hundred videos on a topic I’m not interested in after I watch two or three videos on said topic
• hover autoplay on video thumbnails
• AI summaries in video descriptions, and AI integrations in YouTube Studio
• The transcript button is now in the description for some reason
• YouTube pushing mobile games in their homepage
• Shorts
• silently adding forced midroll ads
• the slight gradient in the progress bar
• there is no way to search a channel’s videos on the mobile app
• There is no way to turn on All subscription notifications in the mobile app without granting the app notification permissions
• no more playlists in the sidebar
• random community posts on the mobile homepage
• live chat button takes up half the horizontal space of the description for some reason

Feel free to share your own.