Meanings of loony fringe in English

Such praise, except from the rightwing loony fringe, is today unthinkable.

He could inspire the right-wing loony fringe to start burning crosses on the lawns of Ashkenazim and Athabascans.

Were they some loony fringe group?

I'd say they were pretty much the loony fringe-thekind of people who would burn down cottages to prove a point.

But biodynamics, once the preserve of the loony fringe, has now moved into the viticultural mainstream with adherents in every corner of the globe.