Script layers_from_fonts.editor_script
Make layers from fonts.
  In the Outline, select a number of fonts from a GUI file, right click on them,
  then pick Make layers with these names.
  Then, after you make sure that the GUI file is saved to disk, right click
  on the root “Gui” node in the Outline and pick Make layers with saved names.
This will create one layer for each font that you initially selected.