Counter for new messages in thunderbird don't counts correctly

[Robin]

If receiving a new message in Thunderbird, a small counter appears in the corner of the icon in the launcher. It disappears if the new message had been opened.
BUT: If receiving more than one messages in one time the counter only disappears if all the new messages had been opened. For example:
You receive 4 new messages : Counter is set 4
You open the first message : Counter is still 4
You open all the residual messages : Counter disappears

Using Thunderbird 14.0 (It's still in Thunderbird 15.0 + 17.0.2)

[Robin (r-ehl)]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:14.0) Gecko/20100101 Firefox/14.0.1
Build ID: 20120713224749

Steps to reproduce:

Receiving more than one e-mail at once. For example 4.

Actual results:

The counter in the launcher is set to the correct number of new messages (4). That's still okay, but then, if I read one of these new messages, the counter still shows the number of messages which had been received at once (4). Only if I read all the new messages, the counter disappears, this is correct.
This don't affects the counter next to the folder-menu in the thunderbird panel.

Expected results:

The counter should have set to 3 if I read one of the new messages.

[Omer Akram (om26er)]

that should be fixed in thunderbird (or is there a separate plugin)

[Robin (r-ehl)]

It's still in thunderbird 15.0…
Lat's wait, perhaps 16.0, with quantal??

[Robin (r-ehl)]

And Version 15, too!

[E-m-cioran (e-m-cioran)]

I can confirm, I have this problem too at POP account (TB version 17, Windows 7). If I click on an received e-mail and the e-mail is after a few seconds automatically marked as readed, the counter after the folder caption regulary (not always) doesn't count down correctly OR Thunderbird doesn't refresh the folder caption. I have to choose another folder firstly, and when I click the previous folder again, then the counter shows the correct value for unreaded e-mails.

If anybody want to try to reproduce this bug:

1. Set, that e-mails are marked as readed after 5 seconds.
2. Create an new e-mail in folder "Drafts".
3. Mark this e-mail as unreaded manually.
4. Click another folder, e. g. "Inbox".

5. Choose folder "Drafts" again. Focus is on e-mail, abd after 5 sec. text-decoration changes from bold to normal.
   BUT: Mostly counter value or caption still is 1!

6. Click on "Inbox" and ...
7. click Drafts folder again. Now the catption changes from "Entwuerfe (1)"/bold to "Entwuerfe"/normal.

This function never had worked correctly at my computer since its implementation in Thunderbird I think.

[Launchpad Janitor (janitor)]

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