> And there are bit flags in the encoder instructions that carry header values that signal they should never be inserted into a dynamic table. My understanding

> And there are bit flags in the encoder instructions that carry header values that signal they should never be inserted into a dynamic table. My understanding is that these header values have to be known to the Qpack implementation beforehand. As a result, it isn't possible for an HTTP/3 client to signal to Qpack to treat a particular custom header as a never-indexed literal.