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(Discontinued) A Firebug extension for Ruby on Rails debugging
JavaScript CSS Shell
Branch: master

This project is discontinued. I'm just not using Firefox, so I have no interest in working on it.

You may fork the code and fix it. Or, rails_panel is a good alternative for Google Chrome.

This codebase is useful as an illustration that Firebug addon development is not much fun. :)

RailsBug - debug Rails apps from Firebug!

Installable via RailsBug @ Firefox Addons.


First, you'll need to set up rack-bug from my branch. It is patched to provide data for this extension. Follow the README there, it's nothing special.

Then, you install this extension into Firefox and off you go!

Credit where credit is due

Two things that made this extension much simpler to code:

  • rack-bug, a Rails debugging toolbar - i used it for the backend as it has a great structure for such a tool.
  • John Resig's Javascript microtemplating microframework - DOMplate is such a mess.


  • refactor code into multiple classes/files
  • make JS templates precompilable
  • employ Sass to make CSS easier
  • automate build process with Rake

(c) 2011 Leonid Shevtsov.

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