In the Tor browser user agent, the "geckotrail" part has been changed.
Apparently following an upstream change in Firefox:
> From Firefox 10 on mobile, geckotrail is the same as firefoxversion.
Note: I'm simply running latest Tor browser on Android and visit
websites showing the user agent to figure out the latest one. I tried to
figure it out from the source code once, but didn't find a place where
it could be looked up trivially (since it gets built of multiple
components etc.).
Related: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent/Firefox
Preferences set with `pref()` can be changed by the user, but they're
then reset on each Firefox startup.
As users may want a different UA and keep it persistent, we should set
the default value with `defaultPref()` instead. This requires moving the
preference to the autoconfig file though, as `defaultPref()` isn't
recognized in the main config file.
Firefox can run an autoconfig Javascript on startup, which can be used to
install and update userChrome.css, both when creating a new profile and
using a pre-existing one.
This removes the need for a wrapper script and related complications
(changes to $PATH, different processing for new and pre-existing
profiles...)
Co-Authored-By: Oliver Smith <ollieparanoid@postmarketos.org>