With Thunderbird, not only new mails are printed as new but all mails in a mailbox. It's easy to determine the new status using the X-Mozilla-Status line. There's a webpage about this http://www.eyrich-net.org/mozilla/X-Mozilla-Status.html (only German). If you need some things translated, drop a note. Reproducible: Always Steps to Reproduce: 1. 2. 3.
Sorry, but I'm not understanding what this bug is about. Could you please describe how you're using the plugin? I'm not sure how it has anything to do with Thunderbird, and I really don't want MUA-specific code in the plugin. (Btw, I guess they actually have their website set up correctly, because that page showed up in English for me ^_~.)
I use Thunderbird with normal (i.e. not IMAP) mailboxes. It's normal mbox format with "From" beginning each message. I expect the mailwatch plugin to show only new messages and not old messages that have been marked as read in the MUA. Even if I delete a message, Thunderbird doesn't delete it in the mailbox but only marks it as deleted. Only if I click "Compress folders", it deletes the from the mbox. That behaviour is normal, other MUAs do the same. Only Mutt deletes the message instantly, resulting in a poor performance if changing mailboxes. I think you can't avoid reading out X-Mozilla-Status if the plugin should be really good. Read the code of Gkrellm (which has a good mailchecker plugin), they do it, too. X-Mozilla-Status hasn't changed across Netscape 4.x, Mozilla, Thunderbird. I hope I described the problem good so that you know what I mean.
Yes, I understand now. But I don't think this is an intended use-case for the plugin. Pasi wrote the mbox support, so it's up to him if he wants to support the mozilla-specific flags. Pasi, feel free to reassign this to yourself if you want, or resolve it WONTFIX if you don't think this makes sense to implement.
Well, without fixing this always new messages are displayed if old messages are in the mailbox. So the plugin would be useless with Thunderbird.
The request is really MUA-specific, but seems quite trivial to implement so I'll look into it.
Of course, it is. But is there a standard method for marking unread and read mail? Just for interest.
Well no, not that I know of. But RFC 2076 does mention "Status:" header as non-standard, but it seems quite commonly used by most MUAs.
Created attachment 224 X-Mozilla-Status patch
That works here very well.
Patch from Pasi for X-Mozilla-Status committed. Reopen if it doesn't work properly.