A Module Is One Row

Decision

A closed module card is one row: its title. The Contains row belongs to the document, which counts its modules in plain words. No count is a filter. Owner ruling 2026-09-16, on sight of the live document canvas, narrowing Container Screens Share One Anatomy and the 2026-09-10 GB-220 arrangement in which every closed container was two rows tall with the Contains row last.

In plain terms: a section heading is one line. The document above it says how many sections it has. Nothing on a card is a button for hiding things.

Why

• The smaller thing gets the smaller card. A module is a part of a document. Two rows under every module name made the module card the heaviest thing on the canvas, above the document that holds it.
• The counts read as a toolbar. Drawn as filters, "2 data blocks" and "1 content block" were two bordered buttons at full width under every module title, outweighing the title itself. Metadata should never look like the card's main action.
• Nobody reached for the filter. Hiding a kind beneath a module was looking-at state for a need that did not arise. A future outline view, a single control at the top right of the canvas that shows headings only, is the right home for any filtering, and is not built yet.

What changed

• ModuleCard drops its contains, hiddenKinds and onToggleContainedKind props and the StackHeaderSubrow that carried them. Its header is the title row and the fold.
• FolioContentsRow is plain words with a dot between, always. Its filter face (hidden, onToggle) is gone.
• The drafting editor keeps no hidden-kinds map. canvasDragRuns and useFolioNavigation take the modules alone; HiddenKindsByModule, NO_HIDDEN_KINDS and isKindHidden are deleted from the arrangement model.
• The document folio and the container cards keep the Contains row as their last row, in words, counting direct children.

Supersedes

• The 2026-09-10 ruling that "on the document canvas a module's counts are filters" (GB-220), and the 2026-09-15 pill treatment for those filters.
• The "two rows tall" statement for every closed container: it now holds for the document and the container tiers, not for the module.