Massage text about the connection preface
Massage prior support caveat
"maintenance frames" only occurred once.
Explicitly draw equivalence to HTTP/1 header fields
"future improvements" -> "variety of flow control algorithms"
shy away from hop/e2e
clarify which stream is being talked about
prioritized stream -> exclusive stream
"the remainder of" doesn't make sense here.

The recipient can't tell where the unpadded payload ends, so
there's no point in making them guess.
awkward sentence
More accurate description of HEADERS
use 'octet' consistently
Specify units for SETTINGs
reduce repetition (see next para)
Make header headers more accurate
Tweak header intros