We are using a similar tensioner as for the jib, as per Kasparek from Australia.
We switched the jib and main halyard exit of the mastbase and just fixed the main tensioner to one of the hiking strap fixation points below the gennaker bag.
We switched the jib and main halyard exit of the mastbase and just fixed the main tensioner to one of the hiking strap fixation points below the gennaker bag.