Chrome extension source viewer (CRX Viewer)

View the source code of any Chrome extension in the Chrome Web store without installing it.
https://chromewebstore.google.com/detail/chrome-extension-source-v/jifpbeccnghkjeaalbbjmodiffmgedin

Also available for Opera and Opera's add-on gallery.
https://addons.opera.com/extensions/details/extension-source-viewer/

And also available for Firefox and addons.mozilla.org (WebExtensions and other Firefox addon types). https://addons.mozilla.org/firefox/addon/crxviewer/

Online demo (select a .crx / .nex / .zip / .xpi from your disk or a URL to try out the viewer):
https://robwu.nl/crxviewer/

Features

This Chrome extension adds a button to right of the omnibox when a CRX file has been detected. This button appears in the following extension stored:

• Chrome Web Store
• Opera add-ons gallery
• Firefox add-ons gallery
• Thunderbird add-ons gallery
• Microsoft Edge Addons store

Upon clicking the button, two actions become available:

• Download extension as zip file
• View source

The default action (showing the above options) can be changed via the "Primary action on click" menu that appears when you right-click on the extension button.

The "View source" option opens a new tab with a simple viewer, with the following features:

• Download-as-zip and download-as-crx at the upper-right corner.
• List of file names, and the option to filter files with a regular expression.
• Find files containing a string, or with content matching a regular expression.
• Quickly jump between search results, or from/to a specific line.
• Automatic beautification (formatting) of code
• Syntax highlighting
• Image preview
• Show hashes (md5, sha1, sha256, sha384, sha512) of the file content.
• View content of embedded zip files.
• Download Chrome Web Store extensions for a different platform (e.g. Chrome OS or NaCl).
• View the contents of any URL or zip file.
• Permalink to file and search result within a zip or extension file.

As mentioned before, this extension activates on the Chrome Web Store by default. It's also possible to view the source code of Chrome, Opera 15+ and Firefox extensions that are hosted elsewhere. Further, there is an option to show a contextmenu entry on links whose target is a Chromium extension. Both features can be toggled at the options page.

Copyright

(c) 2013 - 2026 Rob Wu rob@robwu.nl (https://robwu.nl/)

This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.