No browser I know of falls back to a PNG when given an SVG with a PNG
fallback. The Tor version of my site uses no SVGs.
Exclude the SVG favicon in the Tor version of the site, since the Tor
Browser disables SVG on the safest setting.
The favicon is 175 bytes, smaller than the size of the HTTP headers to
fetch it. It can be inlined.
Now, pages that don't have any other images need just a single request.
Inspired by the h-entry implementation on Charlie Owen's personal
website: https://whalecoiner.com
The u-photo re-uses the 32px favicon that the browser has already
cached, so it shouldn't bloat up the page anymore.
These changes required a bit of additional CSS. I snuck in come color
changes too.
