index.md

---

title: webNavigation.onDOMContentLoaded
slug: Mozilla/Add-ons/WebExtensions/API/webNavigation/onDOMContentLoaded
page-type: webextension-api-event
tags:
  - API
  - Add-ons
  - Event
  - Extensions
  - Non-standard
  - Reference
  - WebExtensions
  - onDOMContentLoaded
  - webNavigation
browser-compat: webextensions.api.webNavigation.onDOMContentLoaded

---

{{AddonSidebar()}}

Fired when the DOMContentLoaded event is fired in the page. At this point the document is loaded and parsed, and the DOM is fully constructed, but linked resources such as images, stylesheets and subframes may not yet be loaded.

Syntax

browser.webNavigation.onDOMContentLoaded.addListener(
  listener,                   // function
  filter                      // optional object
)
browser.webNavigation.onDOMContentLoaded.removeListener(listener)
browser.webNavigation.onDOMContentLoaded.hasListener(listener)

Events have three functions:

• addListener(callback)

  • : Adds a listener to this event.

• removeListener(listener)

  • : Stop listening to this event. The listener argument is the listener to remove.

• hasListener(listener)

  • : Check whether listener is registered for this event. Returns true if it is listening, false otherwise.

addListener syntax

Parameters

• callback

  • : Function that will be called when this event occurs. The function will be passed the following arguments:

    • details

      • : object. Details about the navigation event. See the details section for more information.

• filter {{optional_inline}}

  • : object. An object containing a single property url, which is an {{jsxref("Array")}} of {{WebExtAPIRef("events.UrlFilter")}} objects. If you include this parameter, then the event will fire only for transitions to URLs which match at least one UrlFilter in the array. If you omit this parameter, the event will fire for all transitions.

Additional objects

details

• tabId

  • : integer. The ID of the tab in which the navigation has occurred.

• url

  • : string. The URL to which the given frame has navigated.

• processId

  • : integer. The ID of the process in which this tab is being rendered.

• frameId

  • : integer. Frame in which the navigation is occurring. 0 indicates that navigation happens in the tab's top-level browsing context, not in a nested {{HTMLElement("iframe")}}. A positive value indicates that navigation happens in a nested iframe. Frame IDs are unique for a given tab and process.

• timeStamp

  • : number. The time at which DOMContentLoaded was fired, in milliseconds since the epoch.

Browser compatibility

{{Compat}}

Examples

Logs the target URLs for onDOMContentLoaded, if the target URL's hostname contains "example.com" or starts with "developer".

const filter = {
  url:
  [
    {hostContains: "example.com"},
    {hostPrefix: "developer"}
  ]
}

function logOnDOMContentLoaded(details) {
  console.log(`onDOMContentLoaded: ${details.url}`);
}

browser.webNavigation.onDOMContentLoaded.addListener(logOnDOMContentLoaded, filter);

{{WebExtExamples}}

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