styleName was kept on split, so Enter at the end of a heading left a paragraph
carrying it: drawn like a heading, absent from the navigator's outline, exported
as text:p. It is no longer kept there. setParagraphStyle also missed the name
whenever it switched the node type — a following updateAttributes looks for the
new type in the pre-chain state — so it now rides along with setNode. Levels 2–6
never reached that command at all: the digit class built from MAX_HEADING_LEVEL
(10) read as [0-1], so Heading's own Mod-Alt-N took the key and set a level with
no style; that keymap is dropped, running ahead of every plugin binding.
Steffen Becker
a87e7a4ada