List of areas missing support for ECMAScript/JavaScript in major browsers?

Question

Is anyone aware of a definitive list of areas of missing support for ECMAScript/JavaScript in the major browsers (I\'m talking IE7+, Firefox, Chrome, Safari and Opera).

Answer 1

Some commonly referenced sources are

• Great compatibility tables at QuirksMode. Some of them are being updated recently.
• Kangax sums up ES5 support very well.
• Microsoft released reports of IE standards support.
• Can I Use also includes some information about support of a few Javascript APIs.

Answer 2

A popular source many folks use is: http://kangax.github.com/es5-compat-table/

For Mozilla: https://developer.mozilla.org/En/JavaScript/ECMAScript_5_support_in_Mozilla

For Webkit: http://labs.trolltech.com/blogs/2010/01/15/ecmascript-5-and-webkitjavascriptcore/

For IE: http://www.microsoft.com/download/en/details.aspx?id=14170

Answer 3

You might find Thomas Lahn's ECMAScript support matrix useful.

I doubt very much that there is a definitive list of all the bugs, non-conformities or inconsistencies of browsers, even if restricted to some (undefined) set of "major browsers". The usual strategy is to program for standards and use feature detection and documented alternatives to work around known inconsistencies. Then test as widely as reasonable to discover the unknowns.

While browsers frequently introduce new features, they rarely remove old ones without a very long period of deprecation. So well written code should continue to work in new browsers even if if contains feature tests to work around inconsistencies in browsers that are no longer in use.