Firefox 73 for developers 编辑

This article provides information about the changes in Firefox 73 that will affect developers. Firefox 73 was released on February 11, 2020.

Changes for web developers

Developer tools

• CORS errors now appear as errors in the console (and no longer as warnings) giving them the appropriate visibility (bug 1602093).
• Text and regular expression searches in the web console can now be negated by prefixing them with '-' (bug 1291192).

HTML

No changes.

CSS

• We've implemented overscroll-behavior-block and overscroll-behavior-inline, the logical mappings for overscroll-behavior-x and overscroll-behavior-y (bug 833953).

Removals

• The proprietary -moz-touch-enabled media query has been removed (bug 1486964). You should use pointer: coarse instead.

SVG

• The letter-spacing and word-spacing properties now work in SVG (bug 371787). 

MathML

Removals

• The deprecated <mfenced> element has been removed (bug 1603773). Use the <mrow> and <mo> elements instead.

JavaScript

• The yearName and relatedYear fields have been made available in the DateTimeFormat.prototype.formatToParts() method, enabling useful formatting options for CJK calendars (bug 1591664).

APIs

DOM

• The innerWidth and innerHeight properties on Window objects have been updated to return the width and height of the layout viewport in all situations, rather than sometimes being based on the visual viewport. In particular, previously when using Responsive Design Mode, these returned the visual viewport dimensions, causing the behavior to vary from what was expected (bug 1514429).

WebVR

• The deprecated WebVR API—which has been supplanted by WebXR, which supports both augmented and virtual reality applications—now requires a secure context using the HTTPS protocol to operate. This is due to the availability of sensitive input sources that may include private information (bug 1381645).

Removals

• Support for the VideoPlaybackQuality property corruptedVideoFrames, which has been deprecated in the specification, has been removed from Firefox (bug 1602163).

Security

No changes.

WebDriver conformance (Marionette)

• Added WebDriver:Print to print the current page as a PDF document (bug 1604506).
• Webdriver:TakeScreenshot now always captures the top-level browsing context and not the currently-selected browsing context, if no element to capture has been specified (bug 1398087, bug 1606794).
• Using Webdriver:TakeScreenshot's full argument causes the complete page to be captured (bug 1571424).

Changes for add-on developers

API changes

• The sidebarAction.toggle() function has been implemented (bug 1453355).

Manifest changes

No changes.

See also

• Hacks blog post: Firefox 73 is upon us
• Site compatibility for Firefox 73

Older versions

• 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
• Firefox 53 for developers
• Firefox 52 for developers
• Firefox 51 for developers
• Firefox 50 for developers
• Firefox 49 for developers
• Firefox 48 for developers
• Firefox 47 for developers
• Firefox 46 for developers
• Firefox 45 for developers
• Firefox 44 for developers
• Firefox 43 for developers
• Firefox 42 for developers