igrigorik/http-client-hints — pull request #1 by mikewest (2012-12-17 23:45:06+00:00)
Title: Values might be better as semicolon-delimited text.

RFC2616, section 4.2 specifies that HTTP headers appearing multiple
times can be combined with a comma. Both WebKit and Mozilla respect
this, which means that commas ought to be avoided in the text of the
header's value. This patch suggests a semicolon as a reasonable
alternative.