QtWebkit is a port of Apple's Webkit which utilizes the functionality of the Qt cross-platform application framework, while including the improvements Apple made from the original KHTML and KDE.  The RDK platform uses Qt in other areas, such as the Receiver.  The version of Webkit used in the RDK version of the browser is 537.21 (as reported by Javascript).

Summary of supported features:

HTML Support

Supported Features

• HTTPS
• Redirects
• HTTP Cookies (limited support, in-memory only)
• Javascript
• Clipboard (copy-paste)
• Webgl (experimental)
• HTML5 Canvas 
• CSS3 (http://css3test.com/ 48% score)
• CSS3 downloadable fonts
• Websockets
• audio tag (aac, mp3)
• video tag (h.264)
• Flash Player 11.1

Unsupported HTML Features

• uploading files:  type=file of input tag
• downloading files
• popup windows

Limitations

There are no software codecs. Hardware support is limited in a number of processing units, which is one processing unit per a video stream and one processing unit per an audio stream. 

Local/System Fonts

XFINITY Sans TT Cond
XFINITY Sans TT Lgt
XFINITY Sans TT Med
XFINITY Sans TT Med Cond
XFINITY Sans TT Reg
DejaVu Serif 

Flash Plugin Support

Supported Features

• Flash Plugin 11.1
• SWF (Flash 11.1)
• Video should be limited to H.264 due to presence of hardware decode and rendering support
  
  • HW decoded video is displayed in a hardware video plane behind the Flash content. Flash content can composite on top of the video. But flash content cannot be composited below video. There is no support for transparency within the video stream.
  • Other Flash video formats are supported but may not perform adequately due to lack of hardware support.
• Image file formats are Progressive JPEG, and PNG
• Supported audio codecs are MP3, ADPCM, Nellymoser, Speex and AAC.

Limitations

There are no software codecs. Hardware support is limited in a number of processing units, which is one processing unit per a video stream and one processing unit per an audio stream. 

Comparison of QTWebkit CSS Features to other browsers 

The following is a comparison of the CSS features offered by some of the standard browsers, and the RDK QtWebkit.  With the exception of Firefox and IE, the rest of the browsers are all based off of Webkit. A breakdown of the actual features missing can be found in the appendices.  These tests are based on the site:  http://css3test.com/

Comparison of RDK QTWebkit HTML5 features to other browsers

The following is a comparison of the HTML features offered by some of the standard browsers, and the RDK QtWebkit.  With the exception of Firefox and IE, the rest of the browsers are all based off of Webkit. A breakdown of the actual features missing can be found in the appendices.  These tests are based on the site:  https://html5test.com/