Firefox 85 for developers
=========================

This article provides information about the changes in Firefox 85 that will affect developers. Firefox 85 was released on January 26, 2021.

**Note:** See also January brings us Firefox 85 on Mozilla Hacks.

Changes for web developers
--------------------------

### Developer Tools

* Developers can now use the Page Inspector to toggle the `:focus-visible` pseudo-class for the currently selected element (in addition to the pseudo classes that were previously supported: `:hover`, `:active` and `:focus`, `:focus-within`, and `:visited`). (Firefox bug 1617608).
### HTML

* `<link rel="preload">` is now enabled. (Firefox bug 1626997).

#### Removals

* The `<menuitem>` HTML element is no longer available — it has been hidden behind the `dom.menuitem.enabled flag`. (Firefox bug 1680596).
### CSS

* The `:focus-visible` pseudo-class is now enabled. (Firefox bug 1445482).
* The `pinch-zoom` value for the `touch-action` property is now enabled. (Firefox bug 1329241).
### JavaScript

* The `collation` property can now be specified in the options passed to the `Intl.Collator()` constructor (Firefox bug 1670062). This allows developers to write code with greater clarity:

```js
// Old method
let pinyin = new Intl.Collator(["zh-u-co-pinyin"]);
// New method
let pinyin = new Intl.Collator("zh", { collation: "pinyin" });
```

### Plugins

* Flash support has been completely removed from Firefox (Firefox bug 1675349).
### APIs

*No changes.*

### WebDriver conformance (Marionette)

* Fixed a potential page load timeout situation when `WebDriver:ElementClick`
 is called for a link with a `target` other than `_blank` (Firefox bug 1678455).
* Using web element references on browsing contexts other than the originating one now correctly returns a `no such element` error instead of a `stale element reference` error (Firefox bug 1684827).

#### Known bugs

* WebDriver commands following a call to `WebDriver:SwitchToFrame` can fail with a "no such window" error if the frame's content hasn't yet finished loading (Firefox bug 1691348).
* After a cross-group page navigation, accessing a previously-retrieved element might not always raise a "stale element" error, and can also lead to a "no such element" error. To prevent this, set the `marionette.actors.enabled` preference to `false` (Firefox bug 1690308).
Changes for add-on developers
-----------------------------

*No changes.*

Older versions
--------------

* 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
* Firefox 74 for developers
* Firefox 73 for developers
* Firefox 72 for developers
* Firefox 71 for developers
* Firefox 70 for developers
* Firefox 69 for developers
* Firefox 68 for developers
* Firefox 67 for developers
* Firefox 66 for developers
* Firefox 65 for developers
* Firefox 64 for developers
* Firefox 63 for developers
* Firefox 62 for developers
* Firefox 61 for developers
* Firefox 60 for developers
* Firefox 59 for developers
* Firefox 58 for developers
* Firefox 57 for developers
* Firefox 56 for developers
* Firefox 55 for developers
* Firefox 54 for developers