This is YouTube's new notifications pane:
It just clumps everything together in a difficult-to-read manner, and when I click on a notification to try and see the whole text it takes me away from the video I am currently watching, rather than opening in-the-frame like it used to.
Here's what it used to look like, and what it currently looks like everywhere else on google:
How do I get the older notifications pane on YouTube?