It detects all unused CSS selectors from the stylesheet and helps removing unwanted classes from the stylesheet. This Firefox extension “dust me selector” is very useful for keeping your stylesheet clean.
Once you have finished writing CSS, click on the ‘dust me selector’ icon in the status bar and it will find all the unused selectors. As you can see in the above image it provides the line number which you can use as reference to remove the selectors from your stylesheet. Lesser the code smaller the file size! 🙂
Link: Dust-Me Selector
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