Working today on web developer addon of firefox , found some really cool features apart from outline element , edit css , remove cache etc. That means this web developer addon made by chris is a bundle of several other important small firefox addons which you might be missing.

Lets start the list of features and if you are an smart front end developer , you would make use of every feature and uninstall all other equivalent addons.

Feature 1: Edit HTML Live

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Feature 2: Color Picker/info

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Feature 3: Page weight/size

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Feature 4: Show Grid

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Feature 5: Show Ruler/Measure

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Feature 6: Display Window size Live Preview

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Feature 7: Disable All Javascript

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Feature 8: Hide Background Images

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Feature 9: Javascript Debugger

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Interesting.

Cheers!!