If you use the patched mmime to generate format=flowed emails, the following code added to ~/.vimrc will give you a quick visual check that the trailing whitespace is in the right place. Adjust the last two autocommands if you configured a different maildir for drafts of outgoing messages. function! FixIndented() " remove spaces at end of indented lines silent! %s/^\s.*\zs \+$// endfunction function! TextFlowed() setl tw=72 setl fo+=w setl nojs setl nosmartindent setl list set listchars=trail:• endfunction autocmd BufRead,BufNewFile */sent/cur/* call TextFlowed() autocmd BufRead,BufWritePre */sent/cur/* call FixIndented()