WebKit is an open source web browser engine. WebKit is also the name of the Mac OS X system framework engine.
WebKit is an engine (the basic internals) used in a wide variety of Web Browsers and Mac based system framework for Mac OS X and iOS products.
The WebKit group has support or is working on the following functions: HTML, HTML5, SVG, MathML, CSS, DOM. Most of this functionality effects ePub readers that use WebKit as an engine. It also affects emerging readers that support ePub 3.
 Support for HTML and CSS
WebKit support - Web browser supported constructions and by implication ePub supported constructions for tools depending on WebKit.
Tools using WebKit:
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