ui: plan canvas ink extent + the keyboard-first round

Plan canvas (owner report: arrows clipped at the viewBox edge in dist —
measured 14px/20px cuts in the owner's real plans): blockLayout now
unions node boxes with every edge path's control-point hull (a bezier
never leaves it; the layout calls edgePathD with the renderer's exact
inputs). Dagre's node extent stays the floor, so ordinary plans render
byte-identical; the viewBox origin shifts only when ink bulges past
zero. Verified on both real chats; pins use the owner's real
linear-algebra tree (golden-real-data).

Keyboard-first (owner's law: Enter always submits, arrows always cycle;
text fields the only exception):
- Enter guard split (enter-submits): a focused BUTTON keeps native
  Enter only when keyboard-walked (:focus-visible) or inside an open
  overlay (menus/dialogs); pointer-clicked transcript buttons submit,
  preventDefault suppressing the re-activation underneath.
- Focus hygiene (focus-hygiene): pointer clicks on transient controls
  (agent/user thinking toggles, copy, mermaid expand, plan chip) blur
  to body — the state clicking empty space produces.
- Session search owns the walk: Up/Down wrap-cycle the filtered rows,
  Enter opens the walked row or the first match (quick-open), then
  blurs and keeps the query. The Alt-arrow session cycle is RETIRED.
- Registry: model-menu walk/pick entries removed (obvious in-field
  navigation, not settings material); question-dock keys stay
  displayOnly per owner ruling.

Gates: 1489/1489, typecheck, lint. Verified live end-to-end.

components/ai-elements/reasoning.tsx

@@ -1,6 +1,7 @@
 "use client";
 
 import { useControllableState } from "@radix-ui/react-use-controllable-state";
+import { blurAfterPointerClick } from "@/components/focus-hygiene";
 import {
   Collapsible,
   CollapsibleContent,
@@ -159,6 +160,11 @@ export const ReasoningTrigger = memo(
           className
         )}
         {...props}
+        /* FOCUS HYGIENE (owner, keyboard round 2026-10-10): a pointer click
+           on the thinking toggle must not leave focus here — the learner's
+           next Enter submits, it must not re-toggle. Radix composes this
+           with its own toggle handler. */
+        onClick={(e) => blurAfterPointerClick(e)}
       >
         {children ?? (
           <>

components/chat.tsx

@@ -24,6 +24,7 @@ import { artifactRenderers } from "@/components/artifacts";
 import { SubagentSteerCard } from "@/components/artifacts/steer-card";
 import { Composer } from "@/components/composer";
 import { useEnterSubmits } from "@/components/enter-submits";
+import { blurAfterPointerClick } from "@/components/focus-hygiene";
 import { dockStateKey } from "@/components/dock-state-key";
 import { QueuedSteersBody, type QueuedSteerLine } from "@/components/queued-steers";
 import { DictationBar, finishDictation, joinDictation, useDictation } from "@/components/dictation";
@@ -1264,7 +1265,10 @@ export function Chat({
 <button
 							type="button"
 							data-testid="plan-chip"
-							onClick={() => setPlanOpen(true)}
+							onClick={(e) => {
+								blurAfterPointerClick(e);
+								setPlanOpen(true);
+							}}
 							className="lh-no-drag flex shrink-0 cursor-pointer items-center gap-1.5 rounded-full border border-border/80 px-2 py-0.5 text-xs font-medium uppercase tracking-wide text-muted-foreground transition-colors hover:border-border hover:text-foreground"
 						>
 							<WaypointsIcon className="size-3.5 text-primary" aria-hidden />

components/enter-submits.ts

@@ -13,10 +13,23 @@
  * What the window listener refuses to touch:
  * - typing surfaces (input/textarea/select/contenteditable) — the focused
  *   surface owns its Enter (the dock field, the composer, settings);
- * - BUTTONS — Enter on a focused button is its click (keyboard button
- *   semantics: the collapsed Problem bar must expand, not submit);
  * - modified Enter (⇧↵ is a newline, ⌘/Ctrl↵ belongs to the surface).
  *
+ * BUTTONS — the pointer/keyboard split (owner, keyboard round 2026-10-10):
+ * a mouse click on a transcript control (a thinking toggle, a copy button)
+ * leaves focus ON that button; the learner's next Enter must SUBMIT, not
+ * re-activate the toggle — the report that born this rule. But two button
+ * populations keep native Enter-activates:
+ *   1. KEYBOARD-focused buttons — :focus-visible means focus arrived by
+ *      keyboard (the arrow-walked menus; Tab is dead app-wide, so this
+ *      only happens inside overlays);
+ *   2. buttons inside an OPEN OVERLAY — menus walk focus with arrows and
+ *      Enter activates the walked button natively (menu-shell's contract),
+ *      dialogs are their own surfaced layer (the ONE-ESC LAW's layers).
+ * The pointer-clicked transcript button fails both tests → Enter is ours
+ * (preventDefault also suppresses the browser's default activation, so
+ * the toggle does not fire underneath the submit).
+ *
  * The submit callbacks self-guard (empty thinking / canSubmit) — this hook
  * never checks answer validity, only focus honesty.
  */
@@ -24,6 +37,26 @@
 import { useEffect, useRef } from "react";
 import { isTypingSurface } from "@/src/core";
 
+/** Overlay roots whose buttons keep native Enter (hand-rolled menus mark
+ *  themselves data-lh-menu; Radix poppers/dialogs carry their own attrs). */
+const OVERLAY_ROOTS = '[data-lh-menu], [data-radix-popper-content-wrapper], [role="menu"], [role="dialog"]';
+
+/** Pure decision, exported for pins: does a focused BUTTON keep native
+ *  Enter (true) or does Enter belong to submit (false)? */
+export function buttonKeepsNativeEnter(el: HTMLElement): boolean {
+	// Keyboard-walked focus: the menu arrows landed here — Enter activates.
+	// (Guarded: a selector engine without the pseudo — linkedom in the
+	// test harness — degrades to "not keyboard focus", never throws on
+	// every Enter.)
+	try {
+		if (el.matches(":focus-visible")) return true;
+	} catch {
+		// unsupported pseudo — treat as pointer focus
+	}
+	// Inside an open overlay: the overlay owns its keys.
+	return !!el.closest(OVERLAY_ROOTS);
+}
+
 /** Mount-scoped: while the dock is mounted (a problem/question is active),
  *  plain Enter anywhere outside a typing surface or button submits it. */
 export function useEnterSubmits(submit: () => void): void {
@@ -34,7 +67,8 @@ export function useEnterSubmits(submit: () => void): void {
 			if (e.key !== "Enter") return;
 			if (e.metaKey || e.ctrlKey || e.altKey || e.shiftKey) return;
 			if (isTypingSurface(e)) return;
-			if ((e.target as HTMLElement | null)?.tagName === "BUTTON") return;
+			const target = e.target as HTMLElement | null;
+			if (target?.tagName === "BUTTON" && buttonKeepsNativeEnter(target)) return;
 			e.preventDefault();
 			submitRef.current();
 		};

components/focus-hygiene.ts

@@ -0,0 +1,32 @@
+"use client";
+
+/**
+ * FOCUS HYGIENE — transient transcript controls don't keep focus
+ * (owner, keyboard round 2026-10-10). A pointer click on a thinking
+ * toggle, a copy button, a plan chip used to LEAVE focus on that
+ * button; the learner's next Enter then re-activated the toggle
+ * instead of submitting (see enter-submits.ts for the other half of
+ * the fix). Here we restore, after pointer activation, exactly the
+ * state clicking empty transcript space produces: focus falls back to
+ * the body — Enter submits, arrows cycle the question rows, nothing
+ * re-toggles. Deliberately NOT a focus-into-a-text-field: a focused
+ * field would own the arrows as caret moves, against the arrows-always
+ * law (owner, 2026-10-10).
+ *
+ * Keyboard-activated clicks are untouched: e.detail === 0 marks the
+ * synthesized click of Enter/Space on a keyboard-focused button — the
+ * keyboard user keeps their focus.
+ */
+
+/** Attach as (or compose into) a transient control's onClick: blurs the
+ *  control after POINTER clicks (keyboard clicks keep focus). Node-safe
+ *  duck-typing — no HTMLElement global needed (the test harness runs
+ *  bare node with linkedom). */
+export function blurAfterPointerClick(e: {
+	detail: number;
+	currentTarget: EventTarget | null;
+}): void {
+	if (e.detail === 0) return;
+	const el = e.currentTarget as { blur?: unknown } | null;
+	if (el && typeof el.blur === "function") (el.blur as () => void).call(el);
+}

components/md-blocks.tsx

@@ -39,6 +39,7 @@ import {
 import type { ExtraProps } from "streamdown";
 import { MERMAID_FONT_SIZE, renderMermaid } from "@/components/mermaid-render";
 import { MermaidError } from "@/components/mermaid-error";
+import { blurAfterPointerClick } from "@/components/focus-hygiene";
 import { chartSize, useSessionMermaid } from "@/components/session-overlay";
 import { Hint } from "@/components/ui/hint";
 
@@ -101,7 +102,8 @@ export function CopyCorner({
 				aria-label={label}
 				data-testid="md-copy"
 				className="flex size-6 items-center justify-center rounded-md text-muted-foreground/70 opacity-0 transition-opacity hover:bg-accent hover:text-foreground focus-visible:opacity-100 group-hover/md:opacity-100"
-				onClick={() => {
+				onClick={(e) => {
+					blurAfterPointerClick(e);
 					void copyText(getText()).then((ok) => {
 						if (!ok) return;
 						setCopied(true);
@@ -210,7 +212,10 @@ function MermaidInline({ chart }: { chart: string }) {
 						aria-label="Expand diagram"
 						data-testid="md-mermaid-expand"
 												className="flex size-6 items-center justify-center rounded-md text-muted-foreground/70 opacity-0 transition-opacity hover:bg-accent hover:text-foreground group-hover/md:opacity-100"
-						onClick={() => overlay.openMermaid(chart)}
+						onClick={(e) => {
+							blurAfterPointerClick(e);
+							overlay.openMermaid(chart);
+						}}
 					>
 						<MaximizeIcon className="size-3.5" />
 					</button>

components/plan-block.tsx

@@ -189,14 +189,69 @@ export function blockLayout(nodes: readonly LayoutNode[], edges: ReadonlyArray<{
 		const pts: Array<{ x: number; y: number }> | undefined = g.edge(e.from, e.to)?.points;
 		if (pts) edgePts.set(`${e.from}->${e.to}`, pts.map((pt) => ({ x: pt.x, y: pt.y })));
 	}
+	// THE CANVAS MUST COVER THE ARROWS (owner, 2026-10-10): dagre's
+	// graph extent is the NODE bounding box — the edge curves drawn on
+	// top can bow past it (cross-column edges' bezier control points;
+	// measured 14–20px cut on the right in the owner's plans) and the
+	// viewBox clipped them. The ink extent unions the node boxes with
+	// every edge path's control-point hull: a bezier never leaves the
+	// hull of its control points, and parsing the d-string edgePathD
+	// builds (the SAME call the renderer makes, same inputs) bounds every
+	// segment — M, L and C pairs alternate strictly, so even/odd matches
+	// are x/y. Dagre's extent stays the FLOOR: plans whose arrows stay
+	// inside keep byte-identical viewBoxes (no reflow of every pinned
+	// render), and the origin only moves when ink bulges past zero.
+	let inkMinX = Infinity;
+	let inkMinY = Infinity;
+	let inkMaxX = -Infinity;
+	let inkMaxY = -Infinity;
+	const stretch = (px: number, py: number) => {
+		if (px < inkMinX) inkMinX = px;
+		if (py < inkMinY) inkMinY = py;
+		if (px > inkMaxX) inkMaxX = px;
+		if (py > inkMaxY) inkMaxY = py;
+	};
+	for (const n of nodes) {
+		const nx = x.get(n.id);
+		const ny = y.get(n.id);
+		if (nx === undefined || ny === undefined) continue;
+		stretch(nx, ny);
+		stretch(nx + (nodeW.get(n.id) ?? NODE_W_MIN), ny + (nodeH.get(n.id) ?? NODE_H));
+	}
+	for (const e of routed) {
+		const pts = edgePts.get(`${e.from}->${e.to}`);
+		if (!pts) continue;
+		const tx = x.get(e.to);
+		const ty = y.get(e.to);
+		const target =
+			tx !== undefined && ty !== undefined
+				? {
+						x: tx,
+					y: ty,
+					w: nodeW.get(e.to) ?? NODE_W_MIN,
+						h: nodeH.get(e.to) ?? NODE_H,
+					}
+				: undefined;
+		const nums = edgePathD(pts, target).match(/-?\d+(?:\.\d+)?/g);
+		if (!nums) continue;
+		for (let i = 0; i + 1 < nums.length; i += 2) {
+			stretch(parseFloat(nums[i]!), parseFloat(nums[i + 1]!));
+		}
+	}
+	// Dagre coordinates start at 0; only ink past zero on the negative
+	// side moves the origin (viewBox x/y shift with it).
+	const originX = Math.min(0, inkMinX === Infinity ? 0 : inkMinX);
+	const originY = Math.min(0, inkMinY === Infinity ? 0 : inkMinY);
 	return {
 		x,
 		y,
 		nodeH,
 		nodeW,
 		edgePts,
-		width: Math.max(g.graph().width ?? 0, 1),
-		height: Math.max(g.graph().height ?? 0, 1),
+		originX,
+		originY,
+		width: Math.max((g.graph().width ?? 0) - originX, inkMaxX === -Infinity ? 0 : inkMaxX - originX, 1),
+		height: Math.max((g.graph().height ?? 0) - originY, inkMaxY === -Infinity ? 0 : inkMaxY - originY, 1),
 	};
 }
 
@@ -462,9 +517,14 @@ export function PlanDiagram({
 	const h = Math.max(layout.height, 1);
 	const vbW = w + 2 * pad;
 	const vbH = h + 2 * pad;
+	// The origin rides the ink extent (owner, 2026-10-10): an arrow
+	// bulging past zero shifts the viewBox with it instead of clipping.
+	// Zero-origin plans (the ordinary case) render exactly as before.
+	const ox = viewBoxOverride ? 0 : (layout.originX ?? 0);
+	const oy = viewBoxOverride ? 0 : (layout.originY ?? 0);
 	return (
 		<svg
-			viewBox={viewBoxOverride ?? `${-pad} ${-pad} ${vbW} ${vbH}`}
+			viewBox={viewBoxOverride ?? `${ox - pad} ${oy - pad} ${vbW} ${vbH}`}
 			className={`block ${fill ? "h-full w-full" : `h-auto${naturalSize ? "" : " w-full"}`}${textCapScale ? " mx-auto" : ""}`}
 			style={{
 				// The READING font (owner, 2026-09-26) — via the runtime var, NOT

components/sidebar.tsx

@@ -496,14 +496,16 @@ function SessionsSidebar() {
 		[],
 	);
 
-	/* ── Keyboard seams (shortcut wave A, 2026-09-17) ── The sidebar owns
-	   every session-list interaction, so the shortcuts land here: ⌘⇧F
-	   focuses the search field; Alt+↑/↓ cycle the list (opening the sidebar
-	   if it's closed — the keys work from anywhere, like the toggle does);
-	   Alt+Enter opens the selected session. The selection is a row index
-	   into `shown`, so a typed query narrows the cycle to the matches.
-	   Mouse and keyboard coexist: hovering doesn't claim, a click or an
-	   open clears the selection. */
+	/* ── Keyboard seams (shortcut wave A, 2026-09-17; search-walk round
+	   2026-10-10) ── ⌘⇧F focuses the search field — and THE SEARCH OWNS THE
+	   WALK: ↑/↓ cycle the filtered list (wrap — "cycle"), Enter opens the
+	   walked row, or the FIRST match when nothing is walked (owner,
+	   2026-10-10 — the quick-open pattern: ⌘⇧F, type, Enter, done). The
+	   Alt+↑/↓/↵ global cycle was RETIRED the same round: barely used,
+	   felt laggy. The selection is a row index into `shown`, so the walk
+	   follows whatever the query + kind filter leave. Mouse and keyboard
+	   coexist: hovering doesn't claim, a click or an open clears the
+	   selection. */
 	const [kbdIndex, setKbdIndex] = useState<number | null>(null);
 	const searchRef = useRef<HTMLInputElement>(null);
 	const listRef = useRef<HTMLDivElement>(null);
@@ -601,42 +603,6 @@ function SessionsSidebar() {
 		return () => window.removeEventListener("lh:kbd-sessions-search", onFocusSearch);
 	}, [open, toggle]);
 
-	useEffect(() => {
-		const cycle = (dir: 1 | -1) => {
-			setKbdIndex((i) => {
-				const n = shown?.length ?? 0;
-				if (n === 0) return null;
-				if (i === null) return dir === 1 ? 0 : n - 1;
-				return (i + dir + n) % n;
-			});
-		};
-		const onPrev = () => {
-			if (!open) toggle();
-			cycle(-1);
-		};
-		const onNext = () => {
-			if (!open) toggle();
-			cycle(1);
-		};
-		const onOpenSelected = () => {
-			const target = kbdIndex !== null ? shown?.[kbdIndex] : undefined;
-			if (target) {
-				router.push(`/chat/${target.id}`);
-				setKbdIndex(null);
-			}
-		};
-		window.addEventListener("lh:kbd-cycle-session-prev", onPrev);
-		window.addEventListener("lh:kbd-cycle-session-next", onNext);
-		window.addEventListener("lh:kbd-open-session", onOpenSelected);
-		return () => {
-			window.removeEventListener("lh:kbd-cycle-session-prev", onPrev);
-			window.removeEventListener("lh:kbd-cycle-session-next", onNext);
-			window.removeEventListener("lh:kbd-open-session", onOpenSelected);
-		};
-		// kbdIndex is read (not upserted) so Alt+Enter pushes OUTSIDE any
-		// state updater — a router.push inside one is setState-in-render.
-	}, [open, toggle, shown, router, kbdIndex]);
-
 	// Keep the kbd-selected row in view (the rows are the container's only
 	// buttons, so the index matches).
 	useEffect(() => {
@@ -733,14 +699,48 @@ function SessionsSidebar() {
 							ref={searchRef}
 							data-testid="session-search"
 							value={query}
-							onChange={(e) => setQuery(e.target.value)}
-							// Esc leaves the search (owner, keyboard wave): blur back
-							// to normal, and claim the key so the window Esc chain
-							// (dictation / abort) doesn't also fire.
+							onChange={(e) => {
+								setQuery(e.target.value);
+								// The list reorders under the query every keystroke —
+								// a stale walk index would point at the wrong row.
+								setKbdIndex(null);
+							}}
+							// THE SEARCH OWNS THE WALK (owner, 2026-10-10 — the
+							// retired Alt+↑/↓/↵ cycle's successor): ↑/↓ cycle the
+							// filtered rows (wrap), Enter opens the walked row —
+							// or the FIRST match when nothing is walked (the
+							// quick-open pattern) — then blurs (focus returns to
+							// the app per the Enter law; the query stays for
+							// re-searching). Esc leaves the search (owner,
+							// keyboard wave): blur back to normal, and claim the
+							// key so the window Esc chain (dictation / abort)
+							// doesn't also fire.
 							onKeyDown={(e) => {
 								if (e.key === "Escape") {
 									e.stopPropagation();
 									e.currentTarget.blur();
+									return;
+								}
+								// Modified keys belong to the surface (⇧↵ etc.).
+								if (e.metaKey || e.ctrlKey || e.altKey || e.shiftKey) return;
+								const n = shown?.length ?? 0;
+								if (n === 0) return;
+								if (e.key === "ArrowDown" || e.key === "ArrowUp") {
+									// The rows move, not the caret.
+									e.preventDefault();
+									const dir = e.key === "ArrowDown" ? 1 : -1;
+									setKbdIndex((i) =>
+										i === null || i >= n ? (dir === 1 ? 0 : n - 1) : (i + dir + n) % n,
+										);
+									return;
+								}
+								if (e.key === "Enter") {
+									const target = shown![kbdIndex !== null && kbdIndex < n ? kbdIndex : 0];
+									if (!target) return;
+									e.preventDefault();
+									router.push(`/chat/${target.id}`);
+									setKbdIndex(null);
+									e.currentTarget.blur();
 								}
 							}}
 							placeholder="Search…"

components/thinking-block.tsx

@@ -2,6 +2,7 @@
 
 import { useEffect, useRef, useState } from "react";
 import { ChevronDownIcon } from "lucide-react";
+import { blurAfterPointerClick } from "@/components/focus-hygiene";
 import { cn } from "@/lib/utils";
 
 /** The unified user-thinking row (owner round, 2026-10-05): ONE visual
@@ -115,7 +116,10 @@ export function ThinkingBlock({
 			<button
 				type="button"
 				data-testid={testId ? `${testId}-trigger` : undefined}
-				onClick={() => setOpen((v) => !v)}
+				onClick={(e) => {
+					setOpen((v) => !v);
+					blurAfterPointerClick(e);
+				}}
 				aria-expanded={open}
 				className="flex w-full items-center gap-2 font-medium uppercase tracking-wide text-muted-foreground transition-colors hover:text-foreground"
 			>

docs/keyboard.md

@@ -47,8 +47,10 @@ second pillar of input).
 | Cycle thinking level | Shift+Tab | `lh:kbd-cycle-thinking` (model-picker.tsx) |
 | Toggle sidebar | ⌘B | `lh:toggle-sidebar` (sidebar.tsx) |
 | Sessions search | ⌘⇧F | `lh:kbd-sessions-search` (sidebar.tsx) |
-| Cycle session | ⌥↑ / ⌥↓ | `lh:kbd-cycle-session-prev/next` (sidebar.tsx) |
-| Open selected session | ⌥Enter | `lh:kbd-open-session` (sidebar.tsx) |
+| Walk search results | ↑ / ↓ *in the search field* | sidebar.tsx (cycles the filtered rows, wraps) |
+| Open search result | Enter *in the search field* | sidebar.tsx (walked row, else the first match) |
+| ~~Cycle session~~ | ~~⌥↑ / ⌥↓~~ | RETIRED (owner, 2026-10-10) — the search walk above replaces it |
+| ~~Open selected session~~ | ~~⌥Enter~~ | RETIRED (owner, 2026-10-10) — the search Enter above replaces it |
 | Jump to graph (home) | ⌘G | router.push in keyboard-shortcuts.tsx |
 | New session | ⌘N | router.push in keyboard-shortcuts.tsx |
 | Rename session | F2 | `lh:kbd-rename-session` (chat.tsx) |
@@ -57,6 +59,9 @@ second pillar of input).
 
 ## Model menu keyboard machine (owner polish, 2026-09-17)
 
+(Removed from the settings/cheat-sheet registry 2026-10-10 — obvious
+in-field navigation; the behavior below is unchanged.)
+
 While the model menu is open, focus stays in the search field and the
 menu owns ↑/↓/Enter inside the input's own handler:
 

src/core/keyboard.ts

@@ -25,16 +25,11 @@ export type KeyAction =
 	| "cycle-thinking"
 	| "toggle-sidebar"
 	| "sessions-search"
-	| "cycle-session-prev"
-	| "cycle-session-next"
-	| "open-session"
 	| "jump-graph"
 	| "new-session"
 	| "rename-session"
 	| "cheat-sheet"
 	| "find"
-	| "model-menu-walk"
-	| "model-menu-pick"
 	| "question-focus"
 	| "question-next-row"
 	| "question-prev-row"
@@ -66,9 +61,10 @@ export const KEYBOARD_ACTIONS: readonly KeyActionDef[] = [
 	{ id: "cycle-thinking", label: "Cycle thinking level", scope: "global", binding: "shift+tab" },
 	{ id: "toggle-sidebar", label: "Toggle sessions sidebar", scope: "global", binding: "mod+b" },
 	{ id: "sessions-search", label: "Search sessions", scope: "global", binding: "mod+shift+f" },
-	{ id: "cycle-session-prev", label: "Previous session", scope: "global", binding: "alt+arrowup" },
-	{ id: "cycle-session-next", label: "Next session", scope: "global", binding: "alt+arrowdown" },
-	{ id: "open-session", label: "Open selected session", scope: "global", binding: "alt+enter" },
+	// (The Alt+↑/↓/↵ session cycle was RETIRED, owner 2026-10-10: barely
+	// used, felt laggy. Session navigation lives IN the search now — ↑/↓
+	// walk the filtered list, Enter opens (first match when nothing
+	// walked) — see sidebar.tsx's search input.)
 	{ id: "jump-graph", label: "Graph view", scope: "global", binding: "mod+g" },
 	{ id: "new-session", label: "New session", scope: "global", binding: "mod+n" },
 	{ id: "rename-session", label: "Rename session", scope: "chat", binding: "f2" },
@@ -82,8 +78,10 @@ export const KEYBOARD_ACTIONS: readonly KeyActionDef[] = [
 	// the keys while a question is expanded; the registry never dispatches
 	// them, so bare arrows stay free everywhere else.
 	{ id: "question-focus", label: "Question · focus thinking ↔ rows", scope: "chat", binding: "tab", displayOnly: true },
-	{ id: "model-menu-walk", label: "Model menu · walk results", scope: "global", binding: "arrowup", displayOnly: true },
-	{ id: "model-menu-pick", label: "Model menu · pick result", scope: "global", binding: "enter", displayOnly: true },
+	// (The model-menu entries — "walk results" ↑/↓, "pick result" ↵ — were
+	// REMOVED, owner 2026-10-10: obvious in-field menu navigation, never
+	// dispatched, never rebindable — not settings material. The menu's own
+	// arrow machine (menu-shell.tsx) is unchanged.)
 	{ id: "question-next-row", label: "Question · next row", scope: "chat", binding: "arrowdown", displayOnly: true },
 	{ id: "question-prev-row", label: "Question · previous row", scope: "chat", binding: "arrowup", displayOnly: true },
 	{ id: "question-pick-row", label: "Question · pick row", scope: "chat", binding: "space", displayOnly: true },

tests/enter-submits.test.ts

@@ -0,0 +1,82 @@
+/**
+ * enter-submits + focus-hygiene — the pointer/keyboard Enter split and the
+ * transient-control blur (owner, keyboard round 2026-10-10).
+ *
+ * The regression this pins: clicking a transcript control (a thinking
+ * toggle) left focus on its <button>; the learner's next Enter re-activated
+ * the toggle instead of submitting. The law now: Enter from a
+ * POINTER-focused transcript button submits (the window listener also
+ * preventDefaults, suppressing the default activation underneath);
+ * keyboard-focused buttons and buttons inside open overlays (menus walk
+ * focus with arrows, dialogs are their own layer) keep native Enter.
+ */
+import assert from "node:assert/strict";
+import { parseHTML } from "linkedom";
+import { describe, it } from "node:test";
+import { buttonKeepsNativeEnter } from "../components/enter-submits.ts";
+import { blurAfterPointerClick } from "../components/focus-hygiene.ts";
+
+const { document } = parseHTML("<html><body></body></html>");
+
+function buttonIn(attrs: Record<string, string>): HTMLElement {
+	const host = document.createElement("div");
+	for (const [k, v] of Object.entries(attrs)) host.setAttribute(k, v);
+	const b = document.createElement("button");
+	b.type = "button";
+	host.appendChild(b);
+	document.body.appendChild(host);
+	return b;
+}
+
+describe("buttonKeepsNativeEnter (the pointer/keyboard Enter split)", () => {
+	it("a transcript button (pointer-focused) does NOT keep native Enter — Enter submits", () => {
+		const b = buttonIn({});
+		assert.equal(buttonKeepsNativeEnter(b), false);
+	});
+
+	it("a keyboard-focused button keeps native Enter (:focus-visible)", () => {
+		const b = buttonIn({});
+		// linkedom lacks the pseudo — stub the one call the helper makes.
+		(b as unknown as { matches: (sel: string) => boolean }).matches = (sel: string) =>
+			sel === ":focus-visible";
+		assert.equal(buttonKeepsNativeEnter(b), true);
+	});
+
+	it("buttons inside overlays keep native Enter: hand-rolled menu, Radix popper, dialog, menu role", () => {
+		assert.equal(buttonKeepsNativeEnter(buttonIn({ "data-lh-menu": "" })), true);
+		assert.equal(
+			buttonKeepsNativeEnter(buttonIn({ "data-radix-popper-content-wrapper": "" })),
+			true,
+		);
+		assert.equal(buttonKeepsNativeEnter(buttonIn({ role: "dialog" })), true);
+		assert.equal(buttonKeepsNativeEnter(buttonIn({ role: "menu" })), true);
+	});
+
+	it("a selector engine without :focus-visible degrades to pointer-focus, never throws", () => {
+		const b = buttonIn({});
+		assert.doesNotThrow(() => buttonKeepsNativeEnter(b));
+		assert.equal(buttonKeepsNativeEnter(b), false);
+	});
+});
+
+describe("blurAfterPointerClick (focus hygiene)", () => {
+	it("a POINTER click (detail > 0) blurs the transient control", () => {
+		const b = buttonIn({});
+		let blurred = false;
+		b.blur = () => {
+			blurred = true;
+		};
+		blurAfterPointerClick({ detail: 1, currentTarget: b });
+		assert.equal(blurred, true);
+	});
+
+	it("a KEYBOARD-activated click (detail 0) keeps focus", () => {
+		const b = buttonIn({});
+		let blurred = false;
+		b.blur = () => {
+			blurred = true;
+		};
+		blurAfterPointerClick({ detail: 0, currentTarget: b });
+		assert.equal(blurred, false);
+	});
+});

tests/keyboard-toggle-sidebar.test.ts

@@ -5,6 +5,7 @@ import {
 	bindingForAction,
 	formatBinding,
 	kbdEventForAction,
+	KEYBOARD_ACTIONS,
 } from "../src/core/keyboard.ts";
 import { kbdEventForAction as kbdEventForActionFromUi } from "../components/keyboard-shortcuts.tsx";
 
@@ -54,4 +55,21 @@ describe("the thinking pill suffix — ⇧⇥ via the registry", () => {
 		assert.equal(actionForBinding("shift+tab"), "cycle-thinking");
 		assert.equal(formatBinding("shift+tab"), "⇧⇥");
 	});
+});
+
+describe("the Alt session cycle is RETIRED (owner, 2026-10-10)", () => {
+	// Barely used, felt laggy — session navigation lives IN the search
+	// now (↑/↓ walk the filtered list, Enter opens; sidebar.tsx).
+	it("⌥↑ / ⌥↓ / ⌥↵ bind to NOTHING — no stray action fires", () => {
+		assert.equal(actionForBinding("alt+arrowup") ?? null, null);
+		assert.equal(actionForBinding("alt+arrowdown") ?? null, null);
+		assert.equal(actionForBinding("alt+enter") ?? null, null);
+	});
+
+	it("the actions are gone from the table (cheat sheet + settings render the registry)", () => {
+		const ids = KEYBOARD_ACTIONS.map((a) => a.id as string);
+		assert.ok(!ids.includes("cycle-session-prev"));
+		assert.ok(!ids.includes("cycle-session-next"));
+		assert.ok(!ids.includes("open-session"));
+	});
 });

tests/plan-window.test.tsx

@@ -2,7 +2,7 @@ import { renderToStaticMarkup } from "react-dom/server";
 import { describe, it } from "node:test";
 import assert from "node:assert/strict";
 import { PlanMarginalia, planExists } from "../components/plan-window.tsx";
-import { blockLayout, type PopupMessage } from "../components/plan-block.tsx";
+import { blockLayout, edgePathD, type LayoutNode, type PopupMessage } from "../components/plan-block.tsx";
 import type { PlanTree } from "../src/core/contracts.ts";
 
 // The plan marginalia: the bare diagram in the dock band's right flank —
@@ -88,3 +88,82 @@ describe("PlanMarginalia render", () => {
 		);
 	});
 });
+
+// ─── The canvas must cover the arrows (owner, 2026-10-10) ────────────────────
+// The owner's REAL linear-algebra plan (chat_mv19m6xe, plan_init's mermaid
+// parsed to nodes/edges — golden fixtures use real data, owner ruling
+// 2026-10-10): a cross-column edge's bezier control points reached x=776
+// while dagre's node-extent width was 754 — 14px of arrow clipped at the
+// viewBox edge (the Hume plan cut 20px the same way).
+const LINEAR_ALGEBRA_NODES: LayoutNode[] = [
+{ id: "vector-space-axioms", title: "What a vector space is" },
+	{ id: "span-basis-dimension", title: "Span, basis, dimension" },
+	{ id: "matrix-as-map", title: "Matrices as maps" },
+	{ id: "elimination-rank", title: "Elimination exposes rank" },
+	{ id: "determinant-volume", title: "Det as volume scaling" },
+	{ id: "orthogonality-complements", title: "Orthogonality and complements" },
+	{ id: "projection-theorem", title: "The projection theorem" },
+	{ id: "transpose-adjoint", title: "The transpose as bridge" },
+	{ id: "normal-equations", title: "Least squares, normal equations" },
+	{ id: "eigen-diagonalization", title: "Eigenvectors as coordinates" },
+	{ id: "spectral-theorem", title: "The spectral theorem" },
+	{ id: "pca-synthesis", title: "Goal: PCA and least-squares derivations" }
+];
+const LINEAR_ALGEBRA_EDGES: ReadonlyArray<{ from: string; to: string }> = [
+{ from: "span-basis-dimension", to: "matrix-as-map" },
+	{ from: "matrix-as-map", to: "elimination-rank" },
+	{ from: "matrix-as-map", to: "determinant-volume" },
+	{ from: "matrix-as-map", to: "orthogonality-complements" },
+	{ from: "span-basis-dimension", to: "orthogonality-complements" },
+	{ from: "orthogonality-complements", to: "projection-theorem" },
+	{ from: "orthogonality-complements", to: "transpose-adjoint" },
+	{ from: "matrix-as-map", to: "transpose-adjoint" },
+	{ from: "projection-theorem", to: "normal-equations" },
+	{ from: "transpose-adjoint", to: "normal-equations" },
+	{ from: "matrix-as-map", to: "normal-equations" },
+	{ from: "determinant-volume", to: "eigen-diagonalization" },
+	{ from: "matrix-as-map", to: "eigen-diagonalization" },
+	{ from: "span-basis-dimension", to: "eigen-diagonalization" },
+	{ from: "eigen-diagonalization", to: "spectral-theorem" },
+	{ from: "transpose-adjoint", to: "spectral-theorem" },
+	{ from: "orthogonality-complements", to: "spectral-theorem" },
+	{ from: "spectral-theorem", to: "pca-synthesis" },
+	{ from: "normal-equations", to: "pca-synthesis" }
+];
+
+describe("blockLayout ink extent", () => {
+	it("covers every edge path's control points — arrows never clip (owner, 2026-10-10)", () => {
+		const L = blockLayout(LINEAR_ALGEBRA_NODES, LINEAR_ALGEBRA_EDGES);
+		// The viewBox extent must reach the furthest control point of
+		// every drawn edge (a bezier never leaves its control-point hull).
+		let ctrlMaxX = -Infinity;
+		for (const e of LINEAR_ALGEBRA_EDGES) {
+			const pts = L.edgePts.get(`${e.from}->${e.to}`);
+			if (!pts) continue;
+			const target = {
+				x: L.x.get(e.to)!,
+				y: L.y.get(e.to)!,
+				w: L.nodeW.get(e.to)!,
+				h: L.nodeH.get(e.to)!,
+			};
+			const nums = edgePathD(pts, target).match(/-?\d+(?:\.\d+)?/g) ?? [];
+			for (let i = 0; i + 1 < nums.length; i += 2)
+				ctrlMaxX = Math.max(ctrlMaxX, parseFloat(nums[i]!));
+		}
+		assert.ok(ctrlMaxX > -Infinity, "the fixture has edges");
+		assert.ok(
+			ctrlMaxX <= (L.originX ?? 0) + L.width + 0.5,
+			`control point ${ctrlMaxX} exceeds the canvas right edge ${(L.originX ?? 0) + L.width}`,
+		);
+	});
+
+	it("the real plan's overhang actually EXTENDS the canvas past the node extent", () => {
+		const L = blockLayout(LINEAR_ALGEBRA_NODES, LINEAR_ALGEBRA_EDGES);
+		let nodeMaxX = -Infinity;
+		for (const n of LINEAR_ALGEBRA_NODES)
+			nodeMaxX = Math.max(nodeMaxX, (L.x.get(n.id) ?? 0) + (L.nodeW.get(n.id) ?? 0));
+		// Pre-fix dagre width was 754 with ink at 776 — width must stay ≥
+		// ink, which here strictly exceeds the node extent.
+		assert.ok(L.width > nodeMaxX + 1, `layout width ${L.width} should exceed node extent ${nodeMaxX}`);
+	});
+});

tests/render-settings.test.tsx

@@ -274,6 +274,10 @@ describe("KeyboardSection (thin SSR)", () => {
 		const html = renderToStaticMarkup(<KeyboardSection />);
 		assert.ok(html.includes("Fixed — part of this screen"));
 		assert.ok(!html.includes(`data-testid="kbd-rebind-question-next-row"`), "surface keys stay put");
-		assert.ok(!html.includes(`data-testid="kbd-rebind-model-menu-pick"`));
+		// The model-menu entries are GONE entirely (owner, 2026-10-10):
+		// obvious in-field navigation, not settings material.
+		assert.ok(!html.includes("Model menu"), "model-menu rows removed");
+		assert.ok(!KEYBOARD_ACTIONS.some((a) => a.id as string === "model-menu-walk"));
+		assert.ok(!KEYBOARD_ACTIONS.some((a) => a.id as string === "model-menu-pick"));
 	});
 });