Regex in STREAM::expression

FYI, I hit this issue recently. I'm not sure I fully understand what a partial match is but regardless, I doubled the value of the buffer, within the HTTP_RESPONSE event:

when HTTP_RESPONSE {
  STREAM::max_matchsize 8192
  STREAM::enable
  ...
}

Note, the actual response payload that was giving me issues was around 64kB. Considering the issue was intermittent, it's possible the buffer relates to all traffic handled by the Virtual Server, not each connection.

Using the STREAM::max_matchsize command in the STREAM_MATCHED event (as I'd seen suggested elsewhere) doesn't work.