Thunderbird cannot filter by invisible attributes/headers when using IMAP

Binary package hint: thunderbird

I think the issue is IMAP only.

I try to filter by Launchpad headers such as "X-Launchpad-Message-Rationale". It does not seem to work. I think this is because IMAP only gets the title date and size info from the server, and does not have access to other headers until the message is completely read.

ProblemType: Bug
Architecture: i386
CheckboxSubmission: 37b6e744530b0903e91adb26018991f0
CheckboxSystem: d00f84de8a555815fa1c4660280da308
Date: Wed Oct 7 18:45:04 2009
DistroRelease: Ubuntu 9.10
NonfreeKernelModules: wl
Package: thunderbird 2.0.0.23+build1+nobinonly-0ubuntu1
ProcEnviron:
 PATH=(custom, user)
 LANG=fr_CA.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-11.38-generic
SourcePackage: thunderbird
Uname: Linux 2.6.31-11-generic i686