[otrs] Lots of empty lines after short notes and mails

Hi, when adding short notes (few lines) or sending short mails (which happens quite often), OTRS (3.0.3) shows those entries with several - unneeded - empty lines at the bottom of the field (see attachment). These lines are not added when the entry is long. There seems to be a minimum field height which I'd like to reduce to save space on my screen. Any idea, where this is configurable or changeable? Thanks in advance frank