User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3 Build Identifier: version 2.0.0.0 (20070326) Refer to bug #328833 - this bug was first reported TB version 1.5 (20051201) but never fixed. When composing a message using ISO characters, upon trigger of the autosave a prompt to -send- the message using UTF-8 is opened. This could easily prompt somebody to cancel and lose the message. This bug should be considered major or critical as it is likely that a user's composition will be lost if he tries to avoid sending the message before he is ready. Reproducible: Always Steps to Reproduce: 1. Composed message using ISO charset 2. Wait for autosave interval Actual Results: Box opens up asking if message should be sent in UTF-8 giving the appearance that Thunderbird is trying to automatically send the message. This window will appear in mid-keystroke while composing the message or will grab focus if user is in any other application on their system.