I think we should remove the Flash package/support entirely for 20.04 LTS. I don’t see any reason to attempt to go for alternatives - it’s usage is way down - let’s let the Flash format die.
20.04 LTS releases at end of April so that means 8 months max of total Flash support
20.04.1 likely releases at end of July so that means having Flash for just 5 months for the majority of users
Namely:
- If possible compile Firefox without any NPAPI support, could also drop gtk2. - Which makes it much nicer to support Wayland
- Drop pepperflashplugin-nonfree package from multiverse (does it even work anymore? )
- Drop flashplugin-installer package from multiverse (might be removed from Debian)
- Drop adobe-flashplugin package from archive.canonical.com - and possible consider retiring that archive entirely for Focal
It doesn’t seem unreasonable to me to say if you need Flash stay on 18.04 LTS an extra 5 months then you might otherwise.