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Converts a relative path within an extension's install directory to a fully-qualified URL.


  path // string


string. A path to a resource within an extension expressed relative to its install directory.

Return value

string. The fully-qualified URL to the resource.

Browser compatibility

ChromeEdgeFirefoxFirefox for AndroidOpera
Basic supportYesYes4548Yes


Given a file packaged with the add-on at "beasts/frog.html", get the full URL like this:

var fullURL = browser.extension.getURL("beasts/frog.html");

// -> something like:
// moz-extension://2c127fa4-62c7-7e4f-90e5-472b45eecfdc/beasts/frog.html

Example extensions


This API is based on Chromium's chrome.extension API. This documentation is derived from extension.json in the Chromium code.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

Document Tags and Contributors

 Contributors to this page: andrewtruongmoz, wbamberg, Makyen
 Last updated by: andrewtruongmoz,