Using Build ID: 2002112804 Steps to reproduce problem: 1. Compose in HTML format 2. Options/Format/Auto Detect 3. Reply to a plain text message At this point, the reply will be automatically converted to plain text 4. Edit/Rewrap Now attempting to send the message triggers the HTML Mail Question

(In reply to comment #0) > At this point, the reply will be automatically converted to plain text ??? You mean an actual plain text composition, or just a fixed-width font in the quotation? I certainly don't see the former; quote with fixed-width font only for text/plain without f=f. > 4. Edit/Rewrap > Now attempting to send the message triggers the HTML Mail Question If the recipient is not in the address book, or is listed with an Unknown received-mail-type preference, then I see the question even without rewrapping, for replies to text/plain (with or without f=f) or text/html. Apparently, having a quote counts as "formatting" for purposes of determining whether or not to prompt. xref bug 57256. Neil, should this be kept open?

What I see is that if you take a simple plain text message, and reply to it, then that quote is not interpreted as requiring HTML, and it will autoconvert to plain text without asking me. But if I run it through rewrap then it will ask me to convert it to plain text, even though it already looks like plain text. If I reply to a reply then sometimes it asks me and sometimes it does not.

Is it possible that the autoconversion takes place because the recipient is listed in your address book as "prefers plain"?

Nice try, but a) I don't edit address cards, they all get collected b) this was a news post, so no recipients involved.

See bug 249082 -- the HTML question is invoked by the presence of <span style="white-space: pre;"> resulting from the Rewrap conversion of <blockquote>.

(In reply to neil@parkwaycc.co.uk from comment #0) > 3. Reply to a plain text message > At this point, the reply will be automatically converted to plain text I'm not seeing this behaviour. Thunderbird 52.1.1 (32-bit) Windows 7 64-bit