Great add-on, my constant companion for years. But with the latest Firefox changes, 2 of its most useful (to me) features - CSS > Display Style Information and Information > View document size - are gone. Workaround! What I did was: a) Downloaded and installed Waterfox (I have v.55), then (b) installed in Waterfox an older version of Webdeveloper from the URL Chris gave: https://addons.mozilla.org/en-US/firefox/addon/web-developer/versions/ I got Version 1.2.13. (c) Make sure you set Waterfox updates to "let you choose whether to install them" and set the webdeveloper add-on to "Automatic updates: off", otherwise you might launch Waterfox one day and find you've got webdeveloper 2. Adding an add-on to Waterfox is the same as for Firefox - you'll get a message saying "add to Firefox", but if you're doing it from Waterfox, it adds it to Waterfox. All of this is just to keep "the old webdeveloper" working, cannot vouch for it being safe.

Oh and... be careful. Waterfox just advised me to update to the new "responsive design" module (or whatever), which I did. And webdeveloper lost half of its tricks. Will have to restore the system, I guess.

בינתיים עובד ניפלא...

I know the "disable javascript" Tab has gone, but I need to put the javascript on. All slideshows and dropdown menus are no more working since update to Firefox Quantum.
How I can remove the web developer tool complete with all settings and restore the basic settings again.

How to get back the toolbar below personnal bar on top of window please ?

Cette extension est un must, définitivement !

like it,but now,have some problem.firefox 55.03 version not showing properly

The web developer is as important to my web design and site management as any of my Adobe software.

It's a shame Firefox screwed up big time with the new add-ons system. It made this awesome plugin useless for me.
I don't and never will use Firefox 57 so i've crawled the internet and installed the 1.2.13 XPI and then blocked updates.

So 5 stars for the old one and 0 stars for Firefox 57

I love that I can have a tool that I can just click and see the code etc from any website or webpage.