Select this option (when enabled) to toggle from the Text editor mode to the Graphical editor mode.
If you have made changes to the document, it will be re-parsed and the Treeview and all editing components will be rebuilt. This will have the effect of closing all open tree branches in this version of the Mapper.
If no changes to the text document have been made, the state of the Graphical editor (which tree nodes are open, etc.) will be left unchanged.
