Jumpable, irritatingly movable buttons? Check. Sticky UI that eats up immense space both at the top (header) and to the left (table of contents)? Check. Tiny narrow line of text in the middle? Check. Buttons not looking like buttons, thus confusing me as to what I may click? Check. The language menu made objectively worse, with more clicks necessary to use than before? Check. Every single change is atrocious, negative, and honestly makes me feel depressed - I will either try to scour Reddit for browser extensions to remove as much of it as possible (no, logged in user things are useless to me as I'm never logged in), or I will leave Wikipedia for good (mental health is more important than knowledge).
Topic on Talk:Reading/Web/Desktop Improvements/Prototype testing/Feedback
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Although I'm not in the dev team, I have good news for you: the dev team is aware and currently working to solve most of the issues you listed. A lot of them were talked about during the last Wikimedia Hackathon a few weeks ago.
The team is looking for detailed user feedback about the different options they have for the next batch of improvements. You can test the prototypes here.