I'm sad to say that Firefox Quantum will remain useless to me until proper session management is restored. But without even the necessary API to enable features that were provided by the "Session Manager" add-on for many years, this still seems to be a long way off.
What a great idea! I would love to see a "save AS disk" option that would let you download a D64 disk image containing the rendered graphics in some appropriate format like KoalaPainter or Amica Paint.
There are some good cross-dev C64 graphics editors out there on the PC - I think most of them will let you import pictures, convert them, then save as PRG (etc) executables you can run on a real C64.
Lab journal for my amateur hardware tinkering. Recently focused on 8-bit home computers.