buglet with insettext (collapsable insets?)

[Jean-Marc Lasgouttes]

I know nobody cares about this kind of bug, but it be  asign of
something worse

1/ create a document with an empty open footnote. 

2/ save it

3/ when going through the (empty) footnote, the document gets the
(changed) status; this does not happen if there is text in the
footnote.

JMarc