When starting xfce4-terminal, with the option to show the menu by default, the size of the the first instance of the terminal window is off by 2 rows. For example, if the default size is 80 x 24, the first terminal opened with menu shown, is 80 x 22. Subsequent terminal windows open at the correct size, as long as there is at least one instance still running. This behavior also affect gnome-terminal: https://bugs.launchpad.net/ubuntu/+source/gnome-terminal/+bug/1009331 In fact, only the first instance of either one is affected.
Fixed in current git version.