I'll bump this to try and get a reply from the Studio team.
I've certainly seen a number of sites with large copyright notices at the top of their source files where it would be nice to be able to fold those away so that you didn't have to hit Page Down every time you opened a file.
Also I had a suggestion a while back for the folding around FUNCTIONS to include the comments above them, particularly when using the Source Documentation Generator. Using this example here
https://4js.com/online_documentation/fjs-fgl-manual-html/User/AutoDoc.html#COMMENTING_FUNCTION #+ Compute the amount of the orders for a given customer
#+
#+ This function calculates the total amount of all orders for the
#+ customer identified by the cust_id number passed as parameter.
#+
#+ @code
#+ DEFINE total DECIMAL(10,2)
#+ CALL total = ordersTotal(r_customer.cust_id)
#+
#+ @param cid Customer identifier
#+
#+ @return The total amount as DECIMAL(10,2)
#+
FUNCTION ordersTotal(cid)
DEFINE cid INTEGER
DEFINE ordtot DECIMAL(10,2)
SELECT SUM(ord_amount) INTO ordtot
FROM orders WHERE orders.cust_id = cid
RETURN ordtot
END FUNCTION
...currently you can only fold 14-20. Whilst I was thinking folding 01-20 in one hit, having 01-13 and 14-20 foldable would be OK, and probably more feasible.
Reuben