>I recently upgraded from 5 to 6 and found that forms and formsets behave a little differently in 5 to 6, so maybe the differences occur from 3 to 6 too. I found that it was best to remove any formsets - if you have them.
The formset would certainly account for the behavior. Remove the modal forms from the set, make them "in top-level," and all should work fine.
The Anonymous Bureaucrat,
and frankly, quite content not to be
a member of either major US political party.