User-Agent: Opera/9.24 (Windows NT 5.2; U; en) Build Identifier: version 3.0a1pre (2008021903) I replied to email and started typing my reply. Suddenly messagebox appeared: Message Compose --------------- The mesage you composed contains characters not found in the selected Character Encoding. While you can choose a different Character Encoding, it is usually save to use Unicode (UTF-8) ... ..... -- Send in UTF-8 / Send anyway / Cancel I suspect that autosave triggered and as a side effect (the mail itself is in english in plain ASCII? Though my From: name contain accented characters) it seems to pop up this dialog box. mailnews.send_default_charset=ISO-8859-2 in my configuration First, the messagebox is misleading (or is the half-written message going to be really sent? It seems that not, when I pressed "send" nothing apparent happened - the message appeared in drafts though). Second, the autosave should be performed without such disruptive messageboxes. Reproducible: Always Steps to Reproduce: 1. Set autosave to small amount (like 1 or 2 minutes) 2. Reply to mail 3. Start typing in your answer. Actual Results: Messagebox appeared. See above. Expected Results: Autosave without asking misleading questions.

Note: I have now noticed strange character in the subject (probably a long dash, I can't see it, as it is only a square - a missing character in my font). So probably this was the cause why the popup window appeared, not my name in headers. While I possibly solved this by setting mailnews.send_default_charset to UTF-8 as workaround on my machine, the bug still remains valid.