#46 Prefs/Main/Shaders/Add Tcl error (Win32)

[Randolf Schultz]

On Win32 the "Add"-button of the Shaders preference
setting generates a Tcl error:
Tcl: Error! no value given for parameter "len" to "balloon_setsplit"
The balloon help for the shaders entry field will display a wrong
value afterwards, which will be corrected when the user clicks
into the entry using the left mouse button.