IM HTTP header as defined in RFC3229#10.5.2.
Quick facts
Description
IM HTTP header as defined in RFC3229#10.5.2.
Syntax
IM: vcdiff
Related status codes
Frequently asked questions
IM HTTP header as defined in RFC3229#10.5.2.
It is classified as a request header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-08-18
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