When you click on a new link, there is an "explosion" animation on the tab where it turns entirely blue for a second. This happens every time you click a link. I'm finding this extremely distracting. I'm sensitive to this kind of stuff so I always try to disable animations on everything I can.
The top bar is also black-ish now rather than the system grey. This looks particularly bad with the new "blue" highlight indicator. The tabs are all square rather than rounded. It all looks pretty hideous.
FWIW, the tab shows the loading progress in blue, so you're seeing the result of quick page loads. Not arguing your experience, just clarifying what is happening.
You might like the "Light" theme, which I think is available by default. That won't do any rounding for you, however.
Labels of background tabs became very transparent. This makes them completely unreadable, as my desktop background is quite dark. So, these tab labels are written with black letters on a dark blue background. So freaking good usability! /s
