Originally it was called the "alpha" build if that wording makes more sense to you. Over the years it's been renamed to "aurora" and now finally "developer". But the gist is that it is an alpha with all that implies. I would not use developer for my daily driver.

I've used it as my daily driver for a very long time. It's very stable and think based on beta given the version number.

> All the latest developer tools in beta, plus experimental features like the Multi-line Console Editor and WebSocket Inspector. (from https://www.mozilla.org/en-US/firefox/developer/)

This is the biggest difference: Beta dev tool and experimental features.

That must be pretty outdated, because I'm on Firefox ESR and I have used the multi-line console editor and WebSocket inspector.

The multi-line console editor is already on stable for me, at least. It's quite good; definitely recommend trying it out.

I use the two just for mental separation between work and personal. You can use tab containers etc but it’s nice have a different icon and app.

I really wish Firefox had the equivalent of Chromium's profile manager instead of having to rely on passing in command line parameters to force the profile selector to appear on start.

Easily selecting an entirely separate profile from within the browser just seems like the right way to handle this from a UX perspective.

I don't know when it appeared, but navigating to about:profiles shows

- Create a New Profile

- a list of the existing profiles

- - for each one of those, a "Launch profile in a New Browser" button for any one that isn't already running

along with "Rename" and "Remove" buttons, so that feels about as full-featured a management screen as one could ask for. The only(?) user-hostile behavior is having to know that about: URL

I think I’ve seen a way to expose this within the UI, maybe it was through an add on. If I find it later I’ll update my comment.

* May have been remembering this: https://addons.mozilla.org/en-US/firefox/addon/profile-switc...

You can configure developer edition to install unsigned addons.

Developer edition is dark mode by default and updates way more often than standard Firefox.

Besides that I'm not really sure.

It tracks the beta channel, and has a few different defaults.