User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.5) Gecko/20091102 Firefox/3.5.5 (.NET CLR 3.5.30729) Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.5) Gecko/20091204 Thunderbird/3.0 If you select an attached file from a message, go to another message, right click in a blank space and select Detach, TB will detach the file from the first message, not from the message you're seeing. This is confusing, and a bit dangerous if you select Delete. Same occurs sometimes with Detach All and Delete All. See the video for a better explaination. Reproducible: Always Steps to Reproduce: 1. open a message with an attached file and select it 2. go to another message 3. right click to detach without select individual files Actual Results: Detach/Delete wrong file(s) Expected Results: Detach/Delete the attachments in the opened message

If I follow your steps I can't detach , I can only save as ..... Can you reproduce in -safe-mode (http://kb.mozillazine.org/Safe_mode) ? When you do that anything at the end of Tools -> Error console ? This WFM on Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1.5) Gecko/20091204 Thunderbird/3.0

Hello, tried now in safe mode, same problem. I have only one addon (Remider Fox). And all the rest is on defaults (no skins, customizations, etc). The Error Console is empty, after the steps.

Confirmed Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a1pre) Gecko/20091215 Lightning/1.1a1pre Shredder/3.1a1pre ID:20091215062043 It happeans because right click not select another attachment: if you first select attachment in 2 mail with left click, all work fine. I agree, could be confusing.

if this is really dataloss (I didn't test), then sev=crit

New info: if you do the steps with a moved or deleted message (the first message, with the first attachment, was moved or deleted), TB creates a new empty message on the original message folder.

This might be an instance of bug 533921. And at the heart of the matter might be bug 472286.

Bug 533291 comment 12 makes it pretty clear to me that this is indeed a DUP; marking as such.

Correcting duplicate bug number.