Compatibility/Mobile/Non Standard Compatibility

Non-standard APIs and Properties required for Web Compatibility

This page contains a list of CSS and DOM properties & APIs required for compatibility with the de-facto (mobile) web.

Each is grouped into a group of relative priority, as perceived by the Web Compat team (based on known issues in Bugzilla and webcompat.com and other investigations).

Parts of this list will eventually make its way into the Compatibility Standard.

This document of WebKit stuff implemented in Microsoft Edge also serves as a guide, though not everything will be as important for Gecko.

CSS properties (presumably including their DOM property equivalent?)

Highest Priority

• Enable CSS Unprefixing Service globally. 1177263

The rest of the properties below could be added to the CSS Unprefixing Service, or aliased natively, depending on what makes the most sense.

High Priority

• webkit-flexbox
• webkit-background* (including gradient)
• webkit-transforms
• webkit-transitions

Medium Priority

• -webkit-appearance (or at least -moz-appearance to behave in the same way)
• background-position-x/y

Lower Priority

• -webkit-device-pixel-ratio
• webkit-border*
• webkit-fullscreen*
• webkit-multicol
• webkit-animation

Super Hard but would fix many cosmetic issues (maybe create more?)

• max-width 100% inside of table (975632 + blockers/dependencies, related, etc)

DOM APIs

High Priority

• window.orientation/orientationchange event
• WebKitCSSMatrix

Medium Priority

• innerText (needs spec work)

Video

• HLS video (.m3u8). Possibly Patent encumbered?