Optional ReadonlyatomOptional ReadonlyattrsOptional ReadonlycontentOptional ReadonlygroupSpace-separated group names this node belongs to (e.g. "block").
Optional ReadonlyinlineOptional ReadonlymarksMarks allowed on inline content: "_" for all (default for textblocks),
"" for none, or space-separated mark names.
Optional ReadonlyparseOptional ReadonlypreservePreserve whitespace verbatim when parsing into this node (code blocks).
Optional Readonlyto
Content expression, e.g.
"block+"or"inline*". Omit for leaf nodes.