My reaction to this was "Oh hello Firebug, old friend" :)
It's not firebug, but it was nice that firebug at the time was installable as an extension or a simple bookmarklet, for just about any page, before "Dev Tools" became integral parts of our modern browsers.
It's not firebug, but it was nice that firebug at the time was installable as an extension or a simple bookmarklet, for just about any page, before "Dev Tools" became integral parts of our modern browsers.
EDIT: Firebug's old page is actually still up with a bit of history: https://getfirebug.com/index.html