ENV:SelectorEditor

 When an error message is shown, there is two buttons you can
 press: "Edit" or "Cancel". If you choose to press the "edit"
 button, an editor will be started and load the script file
 that caused the error.
 
 You can use your favourite editor by setting the env
 variable SelectorEditor to the filename of the editor.
 
 Choose your editor now!
 
 You can also load this editor for any open selector
 window, by pressing Ctrl-E. See Keys.