(This wouldn't be a linux-only issue)

Can you still reproduce?

Yes, I can still reproduce this.
The same filter (normal with move to other local folder, not virtual) in POP account INBOX works fine.

backend issue?

Hi,
now this bug also occurs with normal INBOX filter on POP account.
I attach the message for reference.
I also update the bug title.

Extract from msgFilter.dat:
name="Ubuntu"
enabled="yes"
type="17"
action="Move to folder"
actionValue="mailbox://nobody@Local%20Folders/Computer/Linux/Ubuntu"
condition="OR (all addresses,ends with,launchpad.net) OR (from,ends with,ubuntu.com) OR (from,ends with,ubuntuforums.org) OR (from,ends with,ubuntuusers.de) OR ("list-id",ends with,launchpad.net) OR ("reply-to",ends with,bugs.launchpad.net)"

TB version now is 68.5.0 (64-Bit) from Ubuntu 18.04 repository.

i can confirm this is still a bug in TB 78. very annoying! this was first mentioned 5 years ago...

in my efforts to work around the bug, i can confirm the following :
in a header such as Reply-To: Some Guy <abcdef@mailgun.org>

• the filter rule Reply-To [contains] with a complement of 'Some Guy' works correctly
• the filter rule Reply-To [contains] with a complement consisting of data held within the address brackets [e.g., the string 'mailgun.org'] FAILS.

as there is no Reply-To header in the standard header list for filter rules, i created this rule with the 'Customize...' option. so it seems that, for whatever unfathomable reason, pattern matching stops at the address component of the header for at least one header created with the 'Customize...' option.

(In reply to dave from comment #6)

• the filter rule Reply-To [contains] with a complement of 'Some Guy' works correctly
• the filter rule Reply-To [contains] with a complement consisting of data held within the address brackets [e.g., the string 'mailgun.org'] FAILS.

I think, this would be worth to file a separate bug, as it may concern other filter rules too.