index.md

---

title: management.getPermissionWarningsByManifest()
slug: Mozilla/Add-ons/WebExtensions/API/management/getPermissionWarningsByManifest
page-type: webextension-api-function
tags:
  - API
  - Add-ons
  - Method
  - Reference
  - WebExtensions
  - getPermissionWarningsByManifest
  - management
browser-compat: webextensions.api.management.getPermissionWarningsByManifest

---

{{AddonSidebar()}}

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 standardized 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.

This is an asynchronous function that returns a Promise.

Syntax

let gettingWarnings = browser.management.getPermissionWarningsByManifest(
  manifestString      // string
)

Parameters

• manifestString

  • : string. String containing the manifest file. This must be a valid manifest: for example, it must contain all the mandatory manifest keys.

Return value

A Promise that will be fulfilled with an array of strings, each of which contains the text of a permission warning.

Browser compatibility

{{Compat}}

Examples

Log the permission warnings for the given manifest file:

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

let manifestString = JSON.stringify(manifest);

function gotWarnings(warnings) {
  console.log(warnings);
}

function gotError(error) {
  console.log(`Error: ${error}`);
}

let gettingWarnings = browser.management.getPermissionWarningsByManifest(manifestString);
gettingWarnings.then(gotWarnings, gotError);

{{WebExtExamples}}

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