With the modcore Source feature, modcore allows you to download and inspect the source code of Chrome extensions. Please use this functionality responsibly and in accordance with all applicable laws.
Install the modcore Extension Manager (you can find a quick setup guide here) and pin the extension to Chrome’s extensions toolbar.
Visit the Chrome Web Store and open any extension’s page (the URL should look like: https://chromewebstore.google.com/detail/<extension-name>/<extension-id>).
Right-click the modcore Extension Manager icon and select “Get CRX of this extension.”
Once the download is complete, go to
https://modcoretech.github.io/modcore-source/viewer.html.
Upload the file to view and explore the extension’s source code.
The modcore Source feature was specifically developed to ensure compatibility with the CRX files downloaded by the modcore Extension Manager. However, other tools or websites may also be able to display the contents correctly. Please note that modcore Source is still under active development and may not yet meet all expectations - we are committed to improving it over time.
If you encounter any issues, please report them in our GitHub repository. Thank you!
Important:
“Get CRX of this extension” works only on the Chrome Web Store and not on other platforms offering browser extensions.
Some extensions contain protected or obfuscated source code, and you should not modify such code.
modcore Source 3.0 marks a major step forward for the project, introducing a new name, a refined visual identity, and a more focused feature set. This release is centered around clarity, reliability, and a smoother experience when inspecting extension packages.
With this version, Extension Source Viewer has been renamed to modcore Source. The new name better reflects its role within the broader modcore ecosystem and establishes a clearer identity going forward.
The interface has been completely redesigned with a true black color palette. Every part of the application, including the header, sidebar, editor, and panels, now uses consistent dark tones to create a clean and distraction-free environment.
Typography has also been improved. Geist and Geist Mono are now used throughout the interface, providing better readability and a more modern appearance. The code editor has been updated with a custom dark theme, making syntax easier to distinguish while staying comfortable to look at for longer periods.
Overall, the new design focuses on visual clarity, consistency, and ease of use.
modcore Source 3.0 is now fully focused on Chrome extension packages. The application only accepts .crx files, and other archive formats are no longer supported. This change simplifies the experience and removes unnecessary complexity.
Handling of CRX files has been improved to ensure they are processed correctly. The application can reliably extract the contents of both older and newer CRX formats, even in less common cases. This results in a more stable and predictable workflow when opening extension files.
Support for viewing different file types inside extensions has been significantly expanded. Images are displayed clearly, including small assets such as icons. Audio and video files can be played directly within the interface, making it easier to inspect media without leaving the tool.
Font files and other downloadable assets are presented in a straightforward way, allowing users to quickly access and save them when needed. Less common or binary files are also handled more gracefully, ensuring that all content inside an extension remains accessible.
Special care has been taken to manage temporary resources efficiently, preventing unnecessary memory usage when switching between files.
This release introduces a clearer overview of extension contents. A dedicated statistics view provides insight into the size and structure of a package, helping users understand what an extension contains at a glance.
The manifest file is now presented in a structured and readable format. Instead of raw text, it is displayed as an organized tree, making it easier to navigate and understand configuration details. The manifest is also opened automatically when a file is loaded, allowing users to immediately see the most important information.
Several improvements have been made to make navigation and file inspection more convenient. The sidebar is more informative, and file sizes are visible without needing to open files individually. Managing open files is also easier, with options to quickly close or organize tabs.
The editor experience has been refined to support more flexible reading, including improved handling of long lines. Downloading files directly from the interface is now more straightforward, reducing friction when working with extension contents.
Switching between files is now more seamless. The application remembers where you were within a file, including scroll position and cursor placement. This allows users to continue their work without losing context when navigating between multiple files.
The internal structure of the application has been improved with a stronger focus on safety and consistency. All interface elements are created using safe DOM methods, avoiding practices that could introduce risks. This results in a more secure and maintainable codebase.
Thank you,
modcore
Full Changelog: 2.5...3.0
Learn more about modcore Source 2.5: https://github.com/modcoretech/modcore-source/releases/tag/2.5
Learn more about modcore Source 2.0: https://github.com/modcoretech/modcore-source/releases/tag/2.0
Learn more about modcore Source 1.0: https://github.com/modcoretech/modcore-source/releases/tag/1.0