How to configure Geany to wrap lines?
Press Alt+D and then L to toggle line wrapping on or off.
Line wrapping off
Line wrapping on
Go to Edit
> Preferences
. In the Preferences dialog, go to Editor
> Features
and then check the first checkbox (the one corresponding to "Line wrapping") :
Open the menu Document
and check Line Wrapping
which is the top-most entry in the menu.