Hello Hubert,
It would depend on the version of APP you are using for some areas, but you can still access counters through FOM if you wanted to.
formatting.counters[1] //(xcounter 1 in this case)
Alternatively JS variables are formatting safe unlike traditional global variables, so using a 'template.footnoteCounter' template specific global variable should be fine.
V11.1 page events, display objects or just the formatting log may give you some info on your footnotes.
(Datacopy and tformat have a APP JS FOM API training course for new and existing users if it is of interest)
Best Regards
Chris
www.tformat.com