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Description
While we know the effect of Header (and its general variant that allows modifiers) when used for request headers, we don't have much doc or examples when using Headers '[ ... ] in response headers. Whether the response headers necessarily have to be there or not (no, see noHeader), whether modifiers affect the necessity for headers to be there or not, from server & client perspective, etc.
It would be great to have tests that cover all the cases/angles and a slightly more helpful documentation around this whole topic (in the haddocks for sure and perhaps the tutorial/cookbook?).