1
Ok, I have to respect that.
In my view, it is not clutter, because it is important information.
2
I cannot suggest anything technical for a solution. I just wanted to point out, that a TOC is kind of part of the content. And when the content changes it's size (don't matter how, by zoom or user styles, whatever) the TOC font size should be change equally.
But it was just a suggestion, not more, not less
