Firefox Developer Edition is a version of Mozilla product created specifically for software developers. It has several new features and unique functionality. This version of the browser can actually operate independently of standard Firefox and family browsers like Safari. It borrows the default colors and interface elements from the developer tool set which makes the interface itself easy to use and navigate if you have any experience in development of products in this line.
Some of the new tools, like the Valence add-on, give you access to Firefox developer tools for other browsers. Other notable features include things like Responsive Design View, which lets users change screen sizes in real-time without adjusting size of their browser window. Then, there's the style editor, a tool that lets you edit CSS page styles, to create your own variations and apply existing CSS style sheets to other pages.
Firefox Developer Edition is an all-in-one toolbox for people into browser development. It has all the basic tools and some of the more advanced features one would expect from a software bundle like this.
v68.0 [May 16, 2019]
Developer tools:
- The Console now shows more information about CSS warnings, including a node list of the DOM elements that used the rule (bug 1093953).
- The Network monitor request list allows you to block a specific URL (bug 1151368).
- You can now resend a network request without editing the method, URL, parameters, and headers, using the Resend command on the context menu (bug 1422014).
- You can change the width of the columns in the Network Monitor to suit your workflow (bug 1358414).
- The context menu of the Headers tab now allows you to copy all or some of the header information to the clipboard in JSON format (bug 1442249).
- A button has been added to the rules panel of the Page Inspector that allows you to toggle display of any print media queries (bug 1534984).
- An icon will be displayed next to invalid or unsupported CSS rules in the Rules pane of the Page Inspector (bug 1306054).
- You can delete [local and session storage](https://developer.mozilla.org/en-US/docs/Tools/Storage_Inspector#Local_storage_Session_storage) entries by selecting the item in the storage inspector and pressing the backspace key (bug 1522893).
- The preference that controls the visibility of internal extensions (system add-ons and hidden extensions) on the about:debugging page has been changed from devtools.aboutdebugging.showSystemAddons to devtools.aboutdebugging.showHiddenAddons (bug 1544372).
CSS:
- CSS Scroll Snapping has been updated to the latest version of the specification (bug 1312163) and (bug 1544136), this includes:
-The scroll-padding properties (bug 1373832)
-The scroll-margin properties (bug 1373833)
-scroll-snap-align (bug 1373835)
- The -webkit-line-clamp property has been implemented for compatibility with other browsers (bug 866102).
- Support ::marker pseudo-element (bug 205202) and animation for ::marker pseudos (bug 1538618)
- Change currentcolor to be a computed value (except for color property) (bug 760345).
- Fix support for the ch length unit to match spec (fallback for no '0' glyph, vertical metrics) (bug 282126)
- The counter-set property has been implemented. (bug 1518201)
- Implement list numbering using a built-in "list-item" counter; this fixes list numbering bugs (bug 288704)
- CSS Transforms are now supported in indirectly rendered things e.g.) , , , (bug 1323962).
- While we're keeping the prefixed versions of the various gradient properties (linear-gradient(), radial-gradient(), and repeating-radial-gradient() available for compatibility reasons, we have revised how they're parsed so that they're handled much more like the non-prefixed versions. This does mean that certain existing styles won't work correctly. In particular, the complicated syntax taking both an angle and a position will no longer work, and the to keyword in the parameter is not required for the prefixed gradient properties. You are encouraged to use the standard, non-prefixed gradient properties instead, as they're now widely supported (bug 1547939).
Removals:
- scroll-snap-coordinate, scroll-snap-destination, scroll-snap-type-x and scroll-snap-type-y have been removed.
- The scroll-snap-type property has become a longhand, so the old shorthand syntax like scroll-snap-type:mandatory will stop working. See the Firefox Site Compatability note.
CSS Object Model (CSSOM):
- The legacy rules property and addRule() and removeRule() methods have been added to the CSSStyleSheet interface. These were introduced by Internet Explorer 9 and have never managed to quite be stamped out, so they have been added to improve compatibility with the small percentage of sites that still use them (bug 1545823).
DOM:
- The Visual Viewport API has now been enabled by default on Android (bug 1512813). Adding this API to desktop versions of Firefox is being tracked in bug 1551302.
- The Window feature noreferrer is now supported; if specified, the new window's content is loaded without sharing the hostname, IP address, URL, or other identifying information about the host device (bug 1527287).
- The decode() element on images is now implemented. this can be used to trigger loading and decoding of an image prior to adding it to the DOM (bug 1501794).
- The dispatching of events for non-primary mouse buttons has been made to more closely follow the specification; the click event is no longer sent when non-primary buttons are clicked, instead using auxclick. In addition, dblclick no longer fires for non-primary buttons (bug 1379466).
.jpg)
.png){kind=icon}
