I normally don't give one star reviews (or any review for that matter), but just the fact that this extension doesn't work on localhost gave me the motivation to signup for a mozilla account to leave this review.
I saw one of the devs reply something like "We recommend you use lighthouse for chrome"... doesn't that defeat the purpose of this extension even existing? I don't want chrome, or any of the skynet spyware that's embedded in its binaries. This is why we need to support open-source; these silicon valley monopolies got to go. Gee.

Lighthouse returned error: ERRORED_DOCUMENT_REQUEST. Lighthouse was unable to reliably load the page you requested. Make sure you are testing the correct URL and that the server is properly responding to all requests. (Status code: 401)

Very nice and easy to use! But very often the test fails. I've got no idea why. When I test the site under the original google pagespeed link the test works. Also I have an improvement suggestion: Why do I have to make TWO tests for mobile and desktop? If I go to the google test, I have both in one test.

Consistently reporting wrong information (for ex. "Enable Text Compression") and throwing a warning that it's using an old version of the API for a few months now.

very usefully

This does everything is says it'll do perfectly. However, I did not realize what the intention of this plugin is. I was hoping to get the Chrome DevTools experience in Firefox, but instead all this plugin is is a shortcut to PSI, which is okay I guess, but who really needs a plugin for a shortcut? Not faulting the devs for this, they work really hard, and Lighthouse in Chrome is out of this world, and if Lighthouse would take more than a few devs to maintain in Firefox, I can't blame Google for deciding it's not worth the effort.

Four stars holding out the hope Firefox can a get a true lighthouse experience, and if not what's the point of an extension that's nearly fancy bookmarks? I love Chrome and all their developer tools!

Can't (or won't) analyse localhost

Nice i love this

The whole reason I tried this extension was to measure the performance of my app once I got past the login screen. The site didn't work but a Stack Overflow pointed me to this extension, which I assumed would get the job done.

It did not, as it was still not able to analyze past the login screen. If you need to analyze something protected by authentication, look elsewhere.

Allows one click lighthouse audits which helps put Firefox on par with native Chrome functionality. Thanks to the team for porting this across and making sitespeed audits even easier to complete!