Created attachment 314693 [details]
screenshot showing the problem

The webkit composer does a really bad job of re-wrapping lines when replying. I sent myself a test mail with a bunch of 72-character lines:

Here's a test mail with a bunch of lines that are 72 characters wide, y

If I reply to it with the old composer (in Fedora 20), it just allows the quoted lines to be a bit wider than 72 characters - IIRC, one of the reasons 72 characters is the recommended line length for email in the first place is to allow lots of margin for quoting while keeping quoted text under 80 characters, so this makes perfect sense.

Another option would be to completely rewrap the quoted text carefully so it flows properly.

The new composer doesn't do either of the sensible things, though. It just spills over the last couple of characters of the text onto a new line, so when I reply to the mail, my reply looks like this:

> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y
> Here's a test mail with a bunch of lines that are 72 characters wide,
> y

That's awful. I frequently see this affecting my 'real-world' emails, where my replies have weirdly wrapped lines and look bad.