List of features that are supported by Opera 12 but not by Opera 15 due to the switch to Blink/Chromium:
fixed as of August 19, 2013xhr.responseType = 'json'LinkHTTP headerLinkHTTP header for stylesheets specifically- Pressing
Enterwhen an element withtabindexhas focus should trigger a click - Fragment identifiers in
data:URIs should be handled correctly - CSS gradients with transparency
- Accurate SVG rendering
<img src=foo.svg>wherefoo.svgis an SVG file that contains text looks terribleSupport colors with alpha in SVGstopelements andfeFlood(Partial) IDNA 2008 supportTheobject-fitandobject-positionCSS properties- Unprefixed CSS transforms
- DOM attributes should be moved to prototype chains and should expose JavaScript getters/setters
- Protection against regular expression DOS
Object-fit was responsive designer's dream: http://dev.opera.com/articles/view/css3-object-fit-object-position/