Content...
        Content...
        Content...
        Content...
        Content...
        Content...
        etc ( example of fragment of Content )
    

Note for ht-persist:
if you change inner-page, outer-page state will persist.
so try "inner-reload" or "inner-navigate" to another page and come back.
Instructions: just press reload button of this editor page to see state preserved
(it "stays" : if open stays open , if closed stays closed , toggle and reload ).
but remember where state is kept: in the outer-page window object, not in this inner-page window object.