Chrome developer tools : auto-format JavaScript or CSS files
When viewing the source code of minified JavaScript or CSS files in Chrome Developer tools, it is very useful to be able to auto-format them. Chrome developer tools provide a pretty-print option for this purpose.
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Click on the small icon with two curly braces.
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Notice that the pretty-print icon has become blue to indicate that it is active. In the above picture, I am viewing the JS file in the Network tab. In the network tab, as long as the pretty-print button is in an active state, the files will be auto-formatted.
Things work slightly differently in the Sources tab. The pretty-print button is available here as well. But when you click on it, a new tab with the formatted code will open and become active. The old non-formatted tab will remain.