With Firefox 57, non-WebExtensions are not supported so the "Copy Profile" extension [1] no longer works. Since the profile is stored under the application's user ID, it is not accessible on non-root devices. Copy Profile works around this by copying the profile to a non-root space, `/sdcard/mozilla_profile`. Getting the direct data of the profile is extremely useful for analysis (e.g. browser.db); afaict, the WebExtensions API does not support accessing the profile's files directly. As such, we'll have to add code directly to the browser to copy the profile into non-root space. We should make this functionality hard to expose so users don't accidentally copy their data into a place where any applications may see it. Maybe installing an add-on will flip a flag to uncover additional developer menu options such as copy profile? Or an about:config preference (so it's easier to use offline). Or an add-on that flips the about:config preference for you? :) [1]: https://addons.mozilla.org/en-US/android/addon/copy-profile/

Maybe port about:profiles to Fennec and add exporting (and maybe even importing) facilities? But I admit that that would be quite a bit of scope creep, so feel free to disregard this idea. Also while we're looking at it, our profile on Android has spread a little beyond the profile folder itself - the most interesting target to handle in addition would be our shared preferences, at least the global preferences for the whole app and the profile-specific SharedPrefs.

On iOS we hide developer options like this by requiring the version number in Settings to be tapped five times. It's a very handy place to put things.

FYI: copy-profile still works on FF58 but I needed to repair it. Here's my updated version: https://github.com/mcomella/copy-profile

I'd really like to see us build a proper interface to this stuff, using something like https://github.com/palaima/DebugDrawer. Enable it for local builds, fun and profit. This would not be exposed to shipping builds; or maybe it would be exposed only to Nightly builds.

Re-triaging per https://bugzilla.mozilla.org/show_bug.cgi?id=1473195 Needinfo :susheel if you think this bug should be re-triaged.

We have completed our launch of our new Firefox on Android. The development of the new versions use GitHub for issue tracking. If the bug report still reproduces in a current version of [Firefox on Android nightly](https://play.google.com/store/apps/details?id=org.mozilla.fenix) an issue can be reported at the [Fenix GitHub project](https://github.com/mozilla-mobile/fenix/). If you want to discuss your report please use [Mozilla's chat](https://wiki.mozilla.org/Matrix#Connect_to_Matrix) server https://chat.mozilla.org and join the [#fenix](https://chat.mozilla.org/#/room/#fenix:mozilla.org) channel.