[coffeefirst]

You can! It's far more annoying, but I've been running a few that I've made for myself

In `about:config`, set `xpinstall.signatures.required` to false, and then you can an unsigned bundled extension locally and they'll persist like normal extensions.

[tacotime]

If this is not in the MDN refs anywhere yet, it really should be. I’ve been battling with web-ext for a week now after something mysterious broke that I’ve not yet been able to fix. I’m so glad you posted!

[gnicholas]

It looks like that doesn’t work in the regular version of Firefox – only Nightly, Developer, or one of the unbranded versions. Is that true in your experience?

[fireattack]

You're correct, this doesn't work on stable or beta releases.

[coffeefirst]

Yes, I forgot about this but I'm using the Developer version as my main browser because of that.