feature request: publish a Linux flatpak to flathub.org

[jokeyrhyme]

Howdie, thanks so much for building this app, and thanks in-advance for sharing the source code (when that happens)! <3

I've noticed there's already some ProtonMail apps in flathub:

• https://flathub.org/en-GB/apps/ch.protonmail.protonmail-import-export-app
• https://flathub.org/en-GB/apps/ch.protonmail.protonmail-bridge
• https://flathub.org/en-GB/apps/com.protonvpn.www

It'd be awesome if we could get this mail app into flathub in a first-party-supported manner

Cheers! <3

( related to #1 , #6 , and #11 )

[TingPing]

For context flatpaks are a cross-distribution package format, so you don't need an rpm/deb that only work on very specific distros.

Some notes of what needs to be done for this:

• Choose an app id, like ch.protonmail.inbox-desktop, rename the .desktop file and icon to match it.
• Move the icon from the legacy dir of pixmaps to share/icons/hicolor/$SIZE/apps. Ideally add more icon sizes.
• Create an appstream file: https://www.freedesktop.org/software/appstream/docs/index.html
  Many examples are on Flathub (https://github.com/flathub).
  You'll need to select a valid license, it can be proprietary as long as you link to a license.
  Some screenshots will have to be made.
  Install this file, it is not flatpak specific, all stores use it.
  Follow these guidelines: https://docs.flathub.org/docs/for-app-authors/metainfo-guidelines/
• Create the flatpak manifest, electron specific docs are here: https://docs.flatpak.org/en/latest/electron.html
• Submit to Flathub: https://docs.flathub.org/docs/for-app-authors/submission/

I can help if Proton is genuinely interested.