When the user installs or upgrades an add-on, the browser may warn the user about any particularly powerful permissions that the add-on has requested. Not all permissions result in warnings, and this behavior is not standardised across browsers.

Given the text of a manifest.json file, this function returns the permission warnings that would be given for the resulting add-on, as an array of strings.

This API does not require the "management" API permission.

  manifestString,      // string
  function(info) {...} // function

This API is also available as in a version that returns a promise.


string. String containing the manifest file. This must be a valid manifest: for example, it must contain all the mandatory manifest keys.
function. The function is passed the following arguments:
An array of strings, each of which contains the text of a permission warning.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
Basic support Yes No No No Yes


Log the permission warnings for the given manifest file:

var manifest = {
  "manifest_version": 2,
  "name": "test",
  "version": "1.0",
  "permissions": ["management", "<all_urls>"]

var manifestString = JSON.stringify(manifest);

function gotWarnings(warnings) {
  if (chrome.runtime.lastError) {
  } else {
}, gotWarnings);


This API is based on Chromium's API. This documentation is derived from management.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: wbamberg
 Last updated by: wbamberg,