--header
Headers to send with the request. Value should be name and value of the header, separated by a colon.
Example
zshot -H "X-Internal-Header:true" -f shot.png https://example.comDetails
Example: “X-Internal-Header:true”
Headers are sent on every main-frame navigation whose registrable domain (eTLD+1) matches the target’s, so they follow a crawl or navigator session across same-site pages and subdomains. They are not sent on subresource requests or on navigations to a different registrable domain, which keeps custom headers from leaking to third-party hosts. Cookies set with --cookie follow standard cookie-jar rules instead and reach any matching request.