1. Download the .xpi file for the latest release.
  2. In the Jancy application, make sure the web interface is running on the advanced settings page (File → Settings → Advanced). If the web interface is not running when adding the extension, you will see this error message: “There was a problem communicating with Jancy”.

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  1. Start Firefox and navigate to “about:addons”.
  2. Click the “Gear” icon and click “Install Add-on from file”

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  1. Select the .xpi file you downloaded above, and click “Open”.

    Screenshot 2026-08-13 at 3.00.57 PM.png

  2. Click “Open”. The following dialog will appear. If desired, check “allow extension to run in private windows”. Click “Add”.

  3. Your extension should now be running, and you should see the JancyX Sidebar interface appear. Click the extension icon (”boxes” icon) in the far left of the browser window to show/hide the JancyX Sidebar. You can also toggle the Sidebar with a keybind.

    If you are having trouble viewing the Firefox native sidebar (vertical row of icons shown below), see Configure Firefox Toolbar for help.

    Screenshot 2026-08-13 at 3.12.58 PM.png

    (If you see the below error message, it means the extension could not authenticate with Jancy. See Configure Authentication with Jancy for help.)

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