How does one end up in a position to do this work at Mozilla? I'm currently looking for a new SWE role, would absolutely love to work on Firefox.
We do most of our work in the open, so there's a wealth of information you can gather before applying for a role or interviewing. Lurking on mailing lists, reading Bugzilla, following GitHub repos, etc. are all great ways to become familiar with how Mozilla works, the challenges we face, and where you'd best be able to have an impact.
Examples: working from the wrong office (go tell the 70 people fired in Taipei that there will be a steady trickle of opportunities) or under the wrong VP. MoCo is in many aspects a company like any other, with its fair share of Dilbert worthy moments.
Since we're a small team, it's pretty uncommon for a specifically devrel role to open up, but the sibling reply from my teammate callahad is spot-on for how to get involved with Mozilla and Firefox!