Track dynamic change in DOM through Firefox plugin

I was looking for plugin or any means to track change made in HTML DOM dynamically. JavaScript of any kind can change DOM at run time. It is generally difficult to know what got changed and where.

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Finally at one good day I got a Firefox Add-on, which tells me what has changed in DOM and where!
The Add-on is called FireDiff. Download it from here as this is not available on Firefox Add-ons list or it was old Add-on listed there.