User Agent: Mozilla/5.0 (Windows NT 6.0; WOW64; rv:10.0.2) Gecko/20120216 SeaMonkey/2.7.2 Build ID: 20120216055339 Steps to reproduce: Create a plain text message ((i.e. non-HTML) containing some short lines like e.g.: These lines are short. Then mark these lines and type Ctrl-R (rewrap shortcut). Actual results: Nothing happens. Expected results: The marked lines should be rewrapped. The above example should look like this: These lines are short.

I see the same behavior in an old SM 1.1.19 build already, so that's not a regression of any kind for text entered yourself. If that text was entered with "hard" line breaks, it may be the intended behavior to respect those compared to quotes with either no or mixed hard/soft line breaks. On the other hand, one may have copy-pasted that text from somewhere and would like to rewrap it for a nicer display, so that use case wouldn't be applicable with the current implementation (unless pasted as a quotation).

Possibly a duplicate of Bug #187997.