Measurer allows to measure dimensions of the objects on html page. Press down shift for multiple measurements.
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Fangs renders a text version of a web page similar to how a screen reader would read it. The ambition is to help developers understand how an assistive device would present a website and thereby increase chances of finding accessibility issues early.
A suite of tools for developers.
Inspect flash(swf)'s DisplayObject with mouse. Overview the swf's DisplayObject list. Set the inspect filter class when use mouse inspect.
following @itamt on twitter for the updates
Good Website Inspector is an extended ruleset for YSLOW, a Firefox AddOn, to check source codes of HTML pages to get easy and fast hints to optimize the current page.
View xml data in textareas, in readable format.