Most browsers does not accept non-200 and non-407 responses to proxy connection requests for security reasons.
> to proxy connection requests for security reasons. to proxy CONNECT requests for security reasons.
Pull request: https://github.com/WebKit/WebKit/pull/6338
References: https://bugs.chromium.org/p/chromium/issues/detail?id=7338 https://bugzilla.mozilla.org/show_bug.cgi?id=479880
Committed 256639@main (c9f5e13a69fa): <https://commits.webkit.org/256639@main> Reviewed commits have been landed. Closing PR #6338 and removing active labels.
<rdar://problem/102309600>