Sets our main struct and passes it to the parent class.
Create a new #WebKitInputMethodUnderline for the given range in preedit string
Make a copy of the #WebKitInputMethodUnderline.
Free the #WebKitInputMethodUnderline.
Get the main Gtk struct
the main Gtk struct as a void*
Set the color of the underline. If @rgba is %NULL the foreground text color will be used for the underline too.
the main Gtk struct