This page describes the WebExtensions devtools APIs as they exist in Firefox 54. Although the APIs are based on the Chrome devtools APIs, there are still many features that are not yet implemented in Firefox, and therefore are not documented here. To see which features are currently missing please see Limitations of the devtools APIs.

The devtools.panels API lets a devtools add-on define its user interface inside the devtools window.

The devtools window hosts a number of separate tools - the JavaScript Debugger, Network Monitor, and so on. A row of tabs across the top lets the user switch between the different tools. The window hosting each tool's user interface is called a "panel".

With the devtools.panels API you can create new panels in the devtools window.

Like all the devtools APIs, this API is only available to code running in the document defined in the devtools_page manifest.json key, or in other devtools documents created by the add-on (such as the panel's own document). See Extending the developer tools for more.


Represents a devtools panel created by the add-on.


Creates a new devtools panel.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
ExtensionPanel Yes No 54 No Yes
create Yes No 54 No Yes


This API is based on Chromium's chrome.devtools.panels API.

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,