Sideloading Extensions in Microsoft Edge

Whilst there are many extensions available in the Microsoft Edge add-on store, sometimes you need to install one that isn't listed there — or on the Chrome Web Store either. In that case, you can sideload an extension directly from its source files.

This is commonly done by developers whilst building and testing extensions, but it's equally useful for companies that have built internal extensions for their employees and don't want to publish them publicly.

Enable Developer Mode

Open Microsoft Edge and navigate to edge://extensions/ (or open it from the main menu under Extensions).

To sideload an extension you first need to enable Developer Mode using the toggle on the left-hand side of the page. This reveals additional options at the top of the page:

Load the Extension

Click Load unpacked and navigate to the directory containing your extension's source files. The folder you select should contain a manifest.json file — this is what Edge uses to identify the extension and read its metadata.

An unpacked extension is typically a collection of JavaScript, HTML, image files, and other assets, along with that manifest.json.

Once selected, the extension will appear in your installed extensions list under From other sources:

The toggle on the right lets you enable or disable the extension. You can also view its details, remove it, or reload it if the source files have changed.

Using the Extension

Clicking the extensions button in the Edge toolbar will now show your newly installed extension, ready for use:

Clicking the eye icon with a line through it will pin the extension to the toolbar for quick access.

You can sideload any extension this way as long as you have the source code and a valid manifest.json. Only do this for extensions from sources you know and trust.