Extension Developer By: moonbat

About this add-on

This is a fork of Developer Assistant for Firefox. Offers a useful set of tools for XUL developers.

Tools provided


  • Extension Builder: Wizard to package your extension from source directories for distribution.
  • Toggle to enable browser debugging preferences.
  • Javascript tools: Shell, environment (superseded by Scratchpad) and script injector for browser chrome.
  • Live HTML and XUL editors.
  • Regex/Xpath evaluation tools.
  • Best of all - reload browser chrome and skin without restarting the browser. Useful when building your UI or theme.
  • Reload window/restart application.

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Release Information
  • Version: 1.1.5
  • Updated: January 18, 2022

The Epyrus name and related designs, logos, and artwork are Copyright J. Andrews. All rights reserved.
Any other content is copyright or trademark by their respective owners.