Script URL cross site confusion

Question

If i have a script that uses an absolute URL for a script on another website, on which the script say clicked a link what would happen? would a referrer be sent to the destination of the link, and if so would it be from the original site, or from the site where the absolute Url of the script is located? Im sorry if this is confusing, as i reread what i wrote i find myself confused haha. Ill try to illustrate this further.

Site A /
Script 1: ------------------------------------->Site B / Script 2 --------------> Destination site (On Site A, Script 1 references URL of Script 2 on Site B, which clicks a link on Site B)

Your patience and understanding is much appreciated.

Answer 1

The referer header should be set to the URI of the page that the click came from. So, if I understand your example, it would be Site A.

The HTTP spec says:

The Referer[sic] request-header field allows the client to specify, for the server's benefit, the address (URI) of the resource from which the Request-URI was obtained (the "referrer", although the header field is misspelled.) The Referer request-header allows a server to generate lists of back-links to resources for interest, logging, optimized caching, etc. It also allows obsolete or mistyped links to be traced for maintenance. The Referer field MUST NOT be sent if the Request-URI was obtained from a source that does not have its own URI, such as input from the user keyboard.