1. Update according to the changes from upstreams.
2. To build, needed to copy 'document.ico' from 'unofficial' branding
   folder. I believe it has no trademarks attached to it and is OK for
   Parabola as it appears to have no special license notice, meaning it's
   MPL-2.0 as is most of the Firefox code. Ideally, it'd be better to
   remove the wireframe sphere logo from the center and replace it with
   Iceweasel logo, and that's what I did initially. But after some digging
   into license compatibility of MPL-2.0 and multi-license of Iceweasel
   logo (MPL 1.1/GPL 2.0/LGPL 2.1), and reading recommendations to consult
   with a lawyer for this case (combining modified works), I decided that's
   too much of a hassle.
3. FSDG: Disable and remove URLs of Contile and autoupdate of system
   addons.
4. Remove dependencies to old versions of python and python-pydantic,
   since system python-typing-extensions can be used instead of vendored
   one (after removal of it from the source tree in prepare()).
5. Bring back the patch for version constraint of python-zstandard to
   depend on current system version.

Built for x86_64.

Didn't try to build on i686 and armv7h, also didn't check if there were any updates from their upstreams, sorry.