1. Download zip from their github page and make zip.
2. Release date : https://github.com/Modernizr/Modernizr/releases
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1. Download the Development version Uncompressed on the Home page of their site.
2. Since 3.3.1 download build with "Add CSS class" only.
3. Release date : https://github.com/Modernizr/Modernizr/releases
4. Build modernizr from this link https://rejas.uber.space which serves latest version as https://modernizr.com provides older 3.6.0 version, so author himself has suggested to download from the new link. Check this thread :
https://github.com/Modernizr/Modernizr/issues/2508