Version: (using KDE Devel) Installed from: Compiled sources I don't sure kmail is right place for this: kmail internal composer seems to be KDE-wide component, but it is mostly required with kmail itself. I talking about vi-like feature to pipe selected fragment of text through external program like sort(1) or fmt(1). It would be great to have such ability. In addition, it'd be nice to have ability to put presets of such filters in 'Service' menu.
...and have keyboard shortcuts for that ones!
If developers will take a look at bug# 59481, then you wishes (and many other) will be satisfied. Vote for it, please!
*** This bug has been marked as a duplicate of bug 59481 ***