https://docs.themeansar.com/docs/newspaperup-pro/header-option/
Header Option – Docs Themeansar
header optiondocsthemeansar
https://ramaproxy.org/docs/rama/http/layer/header_option_value/index.html
rama::http::layer::header_option_value - Rust
Similar to `super::header_config::HeaderConfigLayer`, but storing the `Default` value of type `T` in case the header with the given `HeaderName` is present and...
header optionramahttplayervalue
https://80x24.org/lore/git/xmqqjzy19coy.fsf@gitster.g/
Re: [PATCH 0/2] send-email: add --header-cmd option - Junio C Hamano