WebKit CSS extensions

Applications based on WebKit or Blink, such as Safari and Chrome, support a number of special WebKit extensions to CSS. These extensions are generally prefixed with -webkit-. Most -webkit- prefixed properties also work with an -apple- prefix. A few are prefixed with -epub-.

WebKit-only properties

Note: Avoid using on websites. These properties will only work in WebKit applications.

A

B

C

D-I

L

M

N

P

R-S

T

U

* A few are on the standards, unprefixed track
** New syntax has been standardized. Property links to the new synax. Old prefixed syntax is still supported in some browsers.

WebKit-prefixed properties on the standards track

Formerly proprietary properties that are now standard

Note: To maximize the compatibility of your CSS, you should use the unprefixed standard properties instead of the prefixed ones listed below.

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B

C

F

G-J

H-L

M

O-R

S

T

U-W

Supported in non-webkit browsers without a prefix, but not standard

The following properties are supported in at least one browser without a prefix, but are not on the standards track.

* Supported unprefixed in Firefox, with prefix in Safari.

Supported in Firefox with -webkit- prefix

The following properties are supported with the -webkit- prefix in Firefox. Many of these are supported with no prefix as well: see Formerly proprietary properties that are now standard above.

Note: Due to the legacy code in a multitude of web sites that used -webkit- prefixed properties, Edge and Firefox redirect many -webkit- prefixed properties to -moz-, -ms-, and unprefixed equivalents.

A

B

F

J

M

O-P

T

U

*Supported with -moz- and -webkit- prefix in Firefox, but not supported without a prefix. Microsoft Edge and IE Mobile support this property with the -webkit- prefix, rather than -ms- for interopability reasons as well.
** These values are supported even though they are not standard and are not on track to becoming standard.
*** Use flex-box properties instead.

Deprecated -webkit- properties

The following properties were once supported with the -webkit- prefix but are no longer supported in evergreen browsers, with or without the -webkit- prefix.

  • -webkit-alt*
  • -webkit-color-correction
  • -webkit-flow-from
  • -webkit-flow-into
  • -webkit-grid-columns (See grid-column)
  • -webkit-grid-rows (See grid-row)
  • -webkit-hyphenate-charset
  • -webkit-image-set (See image-set())
  • -webkit-mask-attachment
  • -webkit-match-nearest-mail-blockquote-color
  • -webkit-overflow-scrolling
  • -webkit-region-break-after
  • -webkit-region-break-before
  • -webkit-region-break-inside
  • -webkit-region-fragment
  • -webkit-shape-inside
  • -webkit-touch-callout (See touch-action)
  • background-origin-x (unprefixed!)
  • background-origin-y (unprefixed!)

* Still supported in the Safari Technology Preview, but not in a generally released browser.

Pseudo-classes

* Now standard.

Note: If there is an invalid pseudo-class within in a chain or group of selectors, the whole selector list is invalid.

Pseudo-elements

For web-compatibility reasons, Blink, WebKit, and Gecko browsers treat all pseudo-elements starting with ::-webkit- as valid.

Note: Generally, if there is an invalid pseudo-element or pseudo-class within in a chain or group of selectors, the whole selector list is invalid. If a pseudo-element (but not pseudo-class) has a -webkit- prefix, As of Firefox 63, Blink, WebKit and Gecko browsers assume it is valid, not invalidating the selector list.

Media features

See also