Similar to what was done for the chromium snap, I am working on enabling a one-time import of existing user profiles by the firefox snap on first run (typically if firefox was installed by another packaging system, such as apt, and used previously).
This requires read-only access to $HOME/.mozilla/firefox
.
The corresponding plug declaration is:
plugs:
[…]
home-dotmozilla-firefox:
interface: personal-files
read: [$HOME/.mozilla/firefox]
[…]
Please consider granting auto-connection as a store assertion.
Note that I am requesting this in anticipation for a feature that hasn’t landed yet: I am working with Mozilla to switch the Firefox snap over to being built from source on Launchpad, and once everything is in place (including the existing profiles import feature), this new snap will replace the current one (which is just a repackaged upstream build) in the store.