extension: Upgrade Firefox to Manifest V3

[danielhjacobs]

This works. The only reason it's a draft is because the onboarding page looks awful.

Manifests have been merged, please test on Chrome as well. If you have Firefox 126 (one below stable), test there too, as it treats host_permissions differently.

[evilpie]

I thought that with Firefox 127 the installation prompt will now include all permissions?

Beginning with Firefox 127, users will be prompted to grant MV3 host permissions as part of the install flow (similar to MV2 extensions). We’re excited to deliver this work as based on feedback from Firefox users and extension developers, this has been a major hurdle for MV3 extensions in Firefox.

https://blog.mozilla.org/addons/2024/05/14/manifest-v3-updates/

[danielhjacobs]

Interesting. Surely we want to keep this working on older Firefox versions though, right? The onboarding page only appears if hasAllUrlsPermission returns false.

[danielhjacobs]

Also the new permissionsButton popup is still nice because it handles the described situation where "MV3 extensions should still leverage the permissions API to ensure that the permissions required are already granted."

[Dinnerbone]

Thank you!

[evilpie]

I wonder if we should highlight this button a bit more, so it's at least more prominent than the "open SWF player" button?

[danielhjacobs]

This can be a follow-up. I'm not good with design. I did move this button to a separate buttons-container div, so that it ends up on a separate line explicitly rather than just by a quirk of the CSS.

[evilpie]

I think this is fine to land as-is. Users running without <all_urls> are probably used to pain.

[evilpie]

Looks ok. If we get complaints about reloading tabs we can still fix it.