> I believe HTTP2 has header compression (RFC 7541)[1] with 'static tables', which seems to be a form of dictionary, but surprisingly to me no html compression with such shared dictionaries.
To my understanding, that static table in HTTP2 is directly in context of recommending and discussing Brotli compression, which does use a table like that as a standard static dictionary in HTTP2+ scenarios including other static dictionary inclusions derived from a corpus of HTML documents.