The Request Header that indicates the initiator of the original Javascript Fetch request. The sec-fetch-dest indicates what source sent this. If any other source sent this not within the list, then the GET is ignored. For example, if we send a GET within a document, then we set a header:
Sec-Fetch-Dest: document
Possible Destinations
Sec-Fetch-Dest: audio
Sec-Fetch-Dest: audioworklet
Sec-Fetch-Dest: document
Sec-Fetch-Dest: embed
Sec-Fetch-Dest: empty
Sec-Fetch-Dest: fencedframe
Sec-Fetch-Dest: font
Sec-Fetch-Dest: frame
Sec-Fetch-Dest: iframe
Sec-Fetch-Dest: image
Sec-Fetch-Dest: manifest
Sec-Fetch-Dest: object
Sec-Fetch-Dest: paintworklet
Sec-Fetch-Dest: report
Sec-Fetch-Dest: script
Sec-Fetch-Dest: serviceworker
Sec-Fetch-Dest: sharedworker
Sec-Fetch-Dest: style
Sec-Fetch-Dest: track
Sec-Fetch-Dest: video
Sec-Fetch-Dest: webidentity
Sec-Fetch-Dest: worker
Sec-Fetch-Dest: xslt