Mozilla Thunderbird FileLink Addon

This is an add-on to be used with Mozilla Thunderbird e-mail program.

It can be installed from Thunderbird's add-ons section, or from the Mozilla add-ons website:

This add-on allows you to easily e-mail large file attachments by uploading those attachments to your FileRun user account and then inserting a web link to the file into the body of your email.

The add-on will not require you to share your FileRun username and password with Thunderbird, but instead it leverages FileRun's OAuth2 server to authorize Thunderbird to perform limited operations on behalf of your FileRun account.

Note: Thunderbird will not have access to any other files and folders and will not be able to perform other operations with your FileRun user account.


  1. Add an API client. Use http://localhost for the redirect URI.
Note: The folder Apps/<API-CLIENT-NAME> needs to be created beforehand inside the user's home folder. This is where the files are going to be uploaded.

Please follow these steps:

  1. Install the add-on
  2. Open Thunderbird's “Options” panel and go to “Attachments”
  3. On the “Outgoing” tab click the “Add” button
  4. Select “FileRun” from the list and fill in the form. The “Server URL” is the FileRun installation URL (make sure you include a trailing slash). The “Client ID” and the “Client Secret” are the ones obtained when configuring the FileRun installation.
  5. Click “Set up Account”.
  6. A popup window will open, showing the FileRun login form.
  7. After logging into FileRun, you will be presented with a consent form which will show you what kind of access is Thunderbird requesting.
  8. Click “Accept”. The popup will close.

You can now start attaching files to your messages with FileRun. To do that, just select “FileRun” from the “Write” panel's “Attach” → “Filelink” menu option.