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Why we use double slash ( // ) instead
https:// from beginig absolute url ? what's different ?
the protocol will be inherited from whichever page you're on. If your site can be on different protocols -
http on the homepage,
https on account pages, for example - then you won't have to worry about potentially loading "insecure content."
The difference is that by not specifying a particular protocol, the script will load using the same protocol used to load the page itself. This has advantages when the page is accessible through more than one protocol (e.g., both
For more information see RFC 3986, Section 5.2: Relative Resolution of URIs.
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