Free Browser Compatibility Testing on Mozilla Firefox 45 Browser Online

ELEMENTS NOT SUPPORTED IN MOZILLA Firefox 45 BROWSER

CSS font-rendering controls

@font-face descriptor (currently defined as font-display) that allows control over how a downloadable font renders before it is fully loaded.

CSS image-set

Method of letting the browser pick the most appropriate CSS background image from a given set, primarily for high PPI screens.

selector list argument of :not()

Selectors Level 4 allows the :not() pseudo-class to accept a list of selectors, which the element must not match any of. Selectors Level 3 only allowed :not() to accept a single simple selector. Thus, :not(a):not(.b):not([c]) can instead be written as :not(a, .b, [c])

CSS Conical Gradients

Method of defining a conical or repeating conical color gradient as a CSS image.

CSS Exclusions Level 1

Exclusions defines how inline content flows around elements. It extends the content wrapping ability of floats to any block-level element.

CSS revert values

A CSS keyword value that resets a property's value to the default specified by the browser in its UA stylesheet, as if the webpage had not included any CSS. For example, display:revert on a

would result in display:block. This is in contrast to the initial value, which is simply defined on a per-property basis, and for display would be inline.

text-emphasis styling

Method of using small symbols next to each glyph to emphasize a run of text, commonly used in East Asian languages. The text-emphasis shorthand, and its text-emphasis-style and text-emphasis-color longhands, can be used to apply marks to the text. The text-emphasis-position property, which inherits separately, allows setting the emphasis marks' position with respect to the text.

CSS3 attr() function for all properties

While attr() is supported for effectively all browsers for the content property, CSS Values and Units Level 3 adds the ability to use attr() onany CSS property, and to use it for non-string values (e.g. numbers, colors).

prefers-reduced-motion media query

CSS media query based on a user preference for preferring reduced motion (animation, etc).

seamless attribute for iframes

The seamless attribute makes an iframe's contents actually part of a page, and adopts the styles from its hosting page. The attribute has been removed from both the WHATWG and the W3C HTML5 specifications.