Rebuild dino master from debian experimental

dino master now has gtk4 support, muc mam and reactions. So I tried to rebuild, but build failed with

/<<PKGBUILDDIR>>/main/src/ui/util/helper.vala:457.5-457.25: error: The name `set_child' does not exist in the context of `Gtk.MenuButton' (gtk4)
    menu_button.set_child(new Image.from_icon_name(icon_name) { pixel_size=pixel_size });
    ^^^^^^^^^^^^^^^^^^^^^

may be the gtk4 version in byzantium is old?