Not always, but it often is. Zoomed to 200% the new design is fine though. Content fills the entire screen and the floating table of contents disappears. Works for me at least.

That suggests to me that you're either not sitting the correct distance away from your display, and/or your display's DPI settings are wrong.

I don't know if there's a "correct" distance, but I do have the monitor set fairly far back. Text is still perfectly readable at 100% it just doesn't fill the screen.

And now the text is huge. Sounds like you either are sitting too far away from your monitor, or need to have your eyes tested if that actually feels comfortable.

The text is huge, but it at least fits with screen. I do have the monitor set back, but not so far that text at 100% is unreadable.