Scrolling past main cursor

When in asciidoc mode I can’t scroll UP past the main cursor. This applies to using view mode (also this discussion) but also using mouse scroll wheel. Now apparently the scroll behaviour has been fixed with #3231, and for most modes (python, kak, md etc) scrolling works.

Now I can’t figure out why asciidoc mode has this scrolling issue. I tried opening a doc and changing the filetype to markdown, but that doesn’t help.