I recently posted about a Firefox / Firebug extension for digging into Firefox's new MozAfterPaint events. I just posted my second update to the Firefox Addons site. In addition to highlighting the clip area of paint events, this update adds screenshots so it's possible to see the page state at the time of an event:

Note that capturing the screen for each paint event adds significant overhead, so it's wise to leave this feature disabled when not actively using it. Other handy features include the ability to view event details on the Firebug DOM tab:

And dig into the complete events details:

The "image" attribute above is a data URL of the screen capture. I imagine this will have some other practical uses. Some other event types are logged for reference, and clicking on any event will reset the base time to the time of that event, to make it easier to see how actions relate to paints:

To use this extension, you will need a 3.1+ Firefox pre-release and Firebug 1.3. You can pick up the latest version of Firebug Paint Events here.

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