Firefox 106 for developers
==========================

This article provides information about the changes in Firefox 106 that will affect developers. Firefox 106 was released on October 18, 2022.

Changes for web developers
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### HTML

* The `<source>` element now supports `height` & `width` attributes when it is a child of a `<picture>` element.
 This functionality is an experimental feature enabled using the `dom.picture_source_dimension_attributes.enabled` preference (Firefox bug 1694741).
### MathML

* The `<semantics>` and `<maction>` MathML elements now only render the first child element by default (Firefox bug 1588733).
### CSS

* The @supports at-rule now supports the `font-tech()` and `font-format()` functions.
 These functions can be used to test whether a browser supports a given font technology or format and CSS styles can be applied based on the result (Firefox bug 1786493).
### JavaScript

No notable changes.

### HTTP

No notable changes.

### Security

No notable changes.

### APIs

#### DOM

* The `HTMLMetaElement.media` property is now supported. This property enables you to set different theme colors based on `media` values (e.g. `max-width: 600px`).
 Meta elements with `media` properties allow the browser to use the `content` value in conjunction with `theme-color` to set the page or UI colors for a given media query (Firefox bug 1706179).
### WebAssembly

No notable changes.

### WebDriver conformance (WebDriver BiDi, Marionette)

#### WebDriver BiDi

* Added basic support for the `script.getRealms` command that is currently limited to the `WindowRealmInfo` type which includes window realms and sandbox realms (Firefox bug 1766240).
* Added support for the `browsingContext.load` event, which is emitted when a `load` event is triggered on a BrowsingContext's window (Firefox bug 1756619).
* Added an object reference store to hold strong references for serialized remote values (Firefox bug 1770736).
* Added support for de-serializing remote references created in the object reference store (Firefox bug 1788124).
* Added full support for the `script.evaluate`, `script.callFunction` and `script.disown` commands (Firefox bug 1778976).

#### Marionette

* Added support for `wheel` input source for Actions, which is associated with a wheel-type input device (Firefox bug 1746601).
* Added support for opening and closing tabs in GeckoView based applications (eg. Firefox for Android) (Firefox bug 1506782).
Changes for add-on developers
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* The ability to set the `"background"` manifest key property `"persistent"` to `false` for Manifest V2 (to make a background page non-persistent) is now available by default.
* The `object-src` directive in the `"content_security_policy"` manifest key is now optional (Firefox bug 1766881). See object-src directive on the `"content_security_policy"` manifest key page for more details.
Older versions
--------------

* Firefox 105 for developers
* Firefox 104 for developers
* Firefox 103 for developers
* Firefox 102 for developers
* Firefox 101 for developers
* Firefox 100 for developers
* Firefox 99 for developers
* Firefox 98 for developers
* Firefox 97 for developers
* Firefox 96 for developers
* Firefox 95 for developers
* Firefox 94 for developers
* Firefox 93 for developers
* Firefox 92 for developers
* Firefox 91 for developers
* Firefox 90 for developers
* Firefox 89 for developers
* Firefox 88 for developers
* Firefox 87 for developers
* Firefox 86 for developers
* Firefox 85 for developers
* Firefox 84 for developers
* Firefox 83 for developers
* Firefox 82 for developers
* Firefox 81 for developers
* Firefox 80 for developers
* Firefox 79 for developers
* Firefox 78 for developers
* Firefox 77 for developers
* Firefox 76 for developers
* Firefox 75 for developers