So, in the old versions of PagePlus X8 and X9, I could Insert > PDF Bookmarks automatically, by choosing which text styles were in which part of the bookmark hierarchy. So Heading 1 would be a main bookmark, and Heading 2 would be a level beneath it. When I exported to PDF (and ticked the Include bookmarks tickbox), I'd get all the bookmarks in my PDF no problem.
I can't find this functionality within Affinity Publisher. Can anyone please point me in the right direction?