HTML embed Quartz Composer removed in Safari 5?

Is it still possible (Lion) to embed Quartz Compositions in web pages (for OSX Safari users)?

The documentation at

https://developer.apple.com/library/archive/documentation/GraphicsImaging/Conceptual/QuartzComposer/qc_webkit/qc_webkit.html

suggests that Quartz Compositions should can be embedded in web pages thus

<embed type="application/x-quartzcomposer"
       src="my_composition.qtz"
       id="myComposition"
       width="300px"
       height="150px"
       opaque="false">
</embed>

but I'm seeing a 'Missing Plugin' message in Safari 5.

Doing Safari > Help > Installed Plug-ins doesn't show a plugin configured to handle .qtz files, but browsing to Library > Internet Plug-ins, I have a copy of Quartz Composer.web开发者_运维知识库plugin

What am I doing wrong?

QuartzComposer.webplugin is based upon the Webkit API. The following comes from the recent Safari Developer notes.

Plug-in Support in Safari 5.1

In Safari 5.1 on Mac OS X 10.7 and 10.6, all browser plug-ins run in their own process, improving browser stability and security. Netscape plug-ins continue to work in Safari with no modification. However, Safari 5.1 does not support WebKit plug-ins. The WebKit plug-in API is not compatible with the new process architecture and is being deprecated. Plug-in developers currently using the WebKit plug-in API should adopt the Netscape plug-in API in order to be compatible with Safari 5.1 on Mac OS X 10.7 and 10.6. You can find the documentation at WebKit Plug-In Programming Topics.

In short, you are doing nothing wrong