Thunderbird fails to work with http proxies

[sachit]

Steps to reproduce:
set the proxy settings manually in thunderbird to any http proxy.
try to set up or open an account.

Results:
Thunderbird fails at password verification.

Expected results:
Thunderbird should connect to the email servers using the http(s) proxy. (using the CONNECT method)

Work around:
Thunderbird (manually set to no-proxy) under proxychains (tunneling data to the http/s proxy ) proxy works just fine.

System:
Thunderbird 17.0.6
Ubuntu 12.04 x64
(even a live boot)

Comments:
1)Try polipo (with tor if necessary) for a proxy that is guaranteed to not have any port blocking issues.

2)The attached file (imap.py) is a perfectly functional minimal imap client that uses ONLY the http CONNECT method of a proxy to reach the gmail server.

2.1)Use this program to verify that
(a) your proxy allows outbound ssl traffic to the server and port
(b) your login credentials and settings for your email account are fine (no unlock captcha problems etc)

2.2)This shows that thunderbird has NO BUSINESS requiring
a) any direct connection, DNS, socks etc.
b) no special proxy server settings – except allowing outbound CONNECT requests to the ports in question. CONNECT requests to a proxy are a prerequisite for https traffic anyway.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.