index.md

---

title: browserSettings.useDocumentFonts
slug: Mozilla/Add-ons/WebExtensions/API/browserSettings/useDocumentFonts
page-type: webextension-api-property
tags:
  - API
  - Add-ons
  - Extensions
  - Property
  - Reference
  - WebExtensions
  - browserSettings
  - useDocumentFonts
browser-compat: webextensions.api.browserSettings.useDocumentFonts

---

{{AddonSidebar()}}

A {{WebExtAPIRef("types.BrowserSetting", "BrowserSetting")}} object whose underlying value is a boolean.

By default, of course, web pages can specify the fonts they want using CSS properties like font-family. This setting enables an extension to instruct Firefox to ignore the fonts specified by the page, and only use system fonts.

Its underlying value is a boolean:

• true: use the fonts specified by the web page. This is the default.

• false: use the system fonts.

Browser compatibility

{{Compat}}

Examples

Set the setting to false:

function logResult(result) {
  console.log(`Setting was modified: ${result}`);
}

browser.browserSettings.useDocumentFonts.set({ value: false }).then(logResult);

{{WebExtExamples}}