diff --git a/PHASE_STATUS_INFLIGHT.md b/PHASE_STATUS_INFLIGHT.md
index 6295f963c..f9cd25bf7 100644
--- a/PHASE_STATUS_INFLIGHT.md
+++ b/PHASE_STATUS_INFLIGHT.md
@@ -3867,3 +3867,88 @@ x-position (x9), same fill, rounded-sm; screenshot confirms the chevron box now
 matches the nav-item box. `tsc` + `next build` (506) clean.
 
 ---
+
+## Stability bug-fix bundle — sidebar refresh/rotate flash + chart crosshair re-park + 2 flaky-test guards (in flight, 2026-05-30)
+
+Three stability fixes on `claude/optimistic-brown-UUcXA`, all post-#325. Two
+are the user-reported sidebar/chart bugs; two are flaky-test hardening
+("เก็บ flaky ให้ครบ"). Frontend + test-only — zero schema / compute / scoring /
+valuation / output-JSON change.
+
+**Bug A — "sidebar opens then shrinks back by itself" on refresh OR
+portrait↔landscape rotation.** Two root causes, two-part fix:
+- The static export bakes the EXPANDED rail into every page's HTML, so on
+  refresh the rail painted wide, then `AppShell`'s mount effect read
+  `localStorage['quantrank.sidebar.collapsed']` and collapsed it — a visible
+  width shrink. Fix: a pre-paint inline `<script>` in `layout.tsx` adds
+  `.sidebar-collapsed` to `<html>` BEFORE the body paints (mirrors next-themes'
+  dark-mode pre-paint), and a new `globals.css` rule
+  (`@media (min-width:768px) html.sidebar-collapsed aside[data-sidebar-rail]`)
+  renders the rail at its collapsed 4rem width immediately → React's
+  post-hydration collapse is a no-op. `AppShell` keeps the class in lockstep
+  with the live state (removed on expand) so the rule never fights React.
+- The aside carried a permanent `width 200ms` transition, so the
+  hydration-collapse AND the breakpoint cross on rotation both ANIMATED the
+  shrink. Fix: a new `animate` flag (owned by `AppShell`, passed to `Sidebar`)
+  is true only for ~250ms around an EXPLICIT user toggle (collapse chevron /
+  mobile hamburger / backdrop); at rest the aside is `transition-none`, so
+  refresh + rotation + resize switch width/position INSTANTLY (no shrink
+  motion). Explicit toggles still animate smoothly.
+
+**Bug B — chart crosshair jumps to the far LEFT when the sidebar is
+expanded/collapsed.** Toggling the rail reflows the main-content width →
+`ResponsiveContainer` re-measures the chart, but Recharts applies `defaultIndex`
+(latest-point park) only on MOUNT, so the crosshair drifted to a stale/left x.
+Fix (`PriceHistoryChart.tsx`): replaced the orientation-only `matchMedia`
+re-park with a width-delta `ResizeObserver` on the chart wrapper that
+debounce-bumps the remount key (`layoutKey`) ~300ms after any width change
+settles → `<AreaChart>` remounts → re-parks at the latest point AFTER the
+re-measure. Subsumes the old orientation listener (rotation changes width too)
+and now also catches sidebar toggle + window resize. A width-only delta gate
+(`<1px → ignore`) prevents height-only / crosshair-render churn from triggering
+spurious remounts. Empirically: cursor x-ratio before=1.0, transient@120ms=0.0
+(the bug), after-repark=1.0 (fixed).
+
+**Flaky-test hardening (เก็บ flaky ให้ครบ):**
+- `test_ranking_history.py::test_load_ranking_history_smoke_recent_window` —
+  added an explicit `if df.empty: pytest.skip(...)` guard (mirrors the
+  `list_ranking_commits` guard from #325 + PR #284). On a shallow CI clone
+  (`actions/checkout` fetch-depth=1) `rankings.json` history may be unreachable
+  → empty frame; the populated-MultiIndex-shape assertions need a full clone.
+  The test previously passed-on-empty only by coincidence of the empty-return
+  path's `.set_index(...)`; the guard makes the shallow-safety explicit +
+  edit-proof (proven via a real depth-1 clone: 46/46 git-dependent tests pass).
+- `test_osap.py::test_package_imports_and_exposes_openap_class` — was a
+  default-lane (non-`@network`) test that instantiated
+  `openassetpricing.OpenAP()`, whose 0.0.2 constructor does a LIVE Google-Drive
+  metadata fetch → flaky whenever Drive rate-limits (returns a "Quota exceeded"
+  HTML page; polars then raises `ColumnNotFoundError` on the missing "Acronym"
+  column — hit live in this session's pre-push gate). Fix: check the API surface
+  on the OpenAP CLASS (`hasattr(openassetpricing.OpenAP, method)`) instead of an
+  instance — the 4 methods are class-level defs, so the scout signal (import
+  resolves + class exposed + methods present) stays in the default offline lane
+  with ZERO network dependency. The live instantiation+fetch path remains
+  covered by the `@network test_fetch_osap_returns_live` in the same file.
+
+**Files** (7): `frontend/app/layout.tsx` (pre-paint script) ·
+`frontend/app/globals.css` (pre-hydration width rule) ·
+`frontend/components/AppShell.tsx` (`animate` flag + class sync) ·
+`frontend/components/Sidebar.tsx` (`animate` prop + `data-sidebar-rail` +
+gated transition) · `frontend/components/PriceHistoryChart.tsx` (ResizeObserver
+re-park) · `tests/test_validation/test_ranking_history.py` +
+`tests/test_ingest/test_osap.py` (flaky guards).
+
+**Verification**: `ruff check .` clean · `pytest -m "not network"` → 1407
+passed (was 1406 + 1 OSAP-flake; now deterministic) · `tsc --noEmit` clean on
+edited files · `next build` → 506 routes · Playwright empirical: A.1 no-flash
+(rail 72px across 62 frames, never wide) / A.2 transition gated (rest→none,
+toggle→width, settle→none) / A.3 rotation instant (transition none, rail 72px) /
+B crosshair re-park (ratio before=1 / transient=0 / after=1) — all PASS.
+
+PHASE_STATUS_INFLIGHT.md side-file satisfies §Conventions "ship with every PR"
+lockstep per PR #237 convention. No CLAUDE.md / AGENTS.md substance change
+required — the fixes don't introduce a new invariant future authors must
+remember beyond what the existing §Gotchas (`overflow-x: clip`, fluid root
+font-size, chart remount-key) already frame.
+
+---
diff --git a/frontend/app/globals.css b/frontend/app/globals.css
index e7a928176..d9bc57031 100644
--- a/frontend/app/globals.css
+++ b/frontend/app/globals.css
@@ -160,6 +160,67 @@ html.dark {
   color-scheme: dark;
 }
 
+/* Pre-hydration sidebar width (Bug A — "the sidebar opens then shrinks back
+ * by itself" on refresh). The static export bakes the EXPANDED sidebar markup
+ * into every page, so on refresh the rail paints at full width, then React
+ * reads localStorage and collapses it — a visible widthward flash. The inline
+ * script in layout.tsx adds `.sidebar-collapsed` to <html> BEFORE paint when
+ * the user's stored choice was collapsed; this rule then renders the rail at
+ * its collapsed width immediately, so React's post-hydration collapse causes
+ * no width change at all. Mirrors how next-themes pre-paints the dark class.
+ * Scoped to md+ — below md the sidebar is an off-canvas drawer, not a rail, so
+ * `collapsed` is a no-op there. `overflow:hidden` clips the not-yet-collapsed
+ * inner labels for the sub-paint moment until React applies the collapsed
+ * layout. AppShell keeps the class in sync with the live collapsed state once
+ * hydrated, so the rule never fights React's width after the app is
+ * interactive (the class is removed the instant the rail is expanded). */
+@media (min-width: 768px) {
+  html.sidebar-collapsed aside[data-sidebar-rail] {
+    width: 4rem;
+    max-width: 4rem;
+    overflow: hidden;
+  }
+  /* Render the FULL collapsed layout pre-hydration, not just the width — else
+   * the expanded inner content (wordmark "QuantRank" + nav labels + section
+   * headers) paints for a frame on a collapsed refresh, then React hydrates
+   * and hides it ("text pops up then disappears"). These rules mirror the
+   * `collapsed ? 'md:…'` Tailwind classes the React tree applies, keyed to the
+   * pre-paint `.sidebar-collapsed` class so the rail looks collapsed from the
+   * FIRST paint. They AGREE with React's classes post-hydration (both collapse
+   * when the class/prop is set, kept in sync by AppShell), so they never fight.
+   * Keep the data-rail values in step with the matching `collapsed ? …` classes
+   * in Sidebar.tsx. */
+  html.sidebar-collapsed [data-rail="hide"] {
+    display: none;
+  }
+  html.sidebar-collapsed [data-rail="show"] {
+    display: flex;
+  }
+  html.sidebar-collapsed [data-rail="header"] {
+    height: auto;
+    flex-direction: column;
+    justify-content: center;
+    gap: 0.375rem; /* md:gap-1.5 */
+    padding: 0.75rem 0.5rem; /* md:py-3 md:px-2 */
+  }
+  html.sidebar-collapsed [data-rail="navlink"] {
+    justify-content: center; /* md:justify-center */
+    padding-left: 0; /* md:px-0 */
+    padding-right: 0;
+  }
+  html.sidebar-collapsed [data-rail="chevron"] {
+    width: 100%; /* md:w-full */
+    height: auto; /* md:h-auto */
+    margin-left: 0; /* drops ml-auto */
+    padding-top: 0.375rem; /* md:py-1.5 */
+    padding-bottom: 0.375rem;
+    background-color: rgb(241 245 249); /* md:bg-slate-100 */
+  }
+  html.dark.sidebar-collapsed [data-rail="chevron"] {
+    background-color: rgb(30 41 59); /* md:dark:bg-slate-800 */
+  }
+}
+
 .font-mono,
 code {
   font-family: var(--font-mono);
diff --git a/frontend/app/layout.tsx b/frontend/app/layout.tsx
index 469503f42..fbb792067 100644
--- a/frontend/app/layout.tsx
+++ b/frontend/app/layout.tsx
@@ -26,6 +26,18 @@ export default function RootLayout({ children }: { children: React.ReactNode })
     // the harmless attr mismatch on <html> needs to be suppressed.
     <html lang="en" suppressHydrationWarning>
       <body>
+        {/* Pre-paint the collapsed sidebar (Bug A). The static export always
+            bakes the EXPANDED rail into the HTML, so without this the rail
+            flashes wide → narrow on refresh once React reads localStorage.
+            Setting the class before the body paints lets globals.css render
+            the collapsed width immediately. Mirrors next-themes' pre-paint
+            dark-mode class; IIFE + try/catch, browser-only, never throws. */}
+        <script
+          dangerouslySetInnerHTML={{
+            __html:
+              "(function(){try{if(localStorage.getItem('quantrank.sidebar.collapsed')==='1'){document.documentElement.classList.add('sidebar-collapsed')}}catch(e){}})()",
+          }}
+        />
         <ThemeProvider>
           <AppShell>{children}</AppShell>
         </ThemeProvider>
diff --git a/frontend/components/AppShell.tsx b/frontend/components/AppShell.tsx
index 1eec22557..778b9f18d 100644
--- a/frontend/components/AppShell.tsx
+++ b/frontend/components/AppShell.tsx
@@ -17,6 +17,13 @@ export function AppShell({ children }: { children: React.ReactNode }) {
   const [collapsed, setCollapsed] = useState(false);
   const [mobileOpen, setMobileOpen] = useState(false);
   const [hydrated, setHydrated] = useState(false);
+  // `animate` gates the sidebar's width/transform transition. It is true ONLY
+  // for the ~250ms around an explicit user toggle (collapse chevron, mobile
+  // hamburger, backdrop). Hydration (refresh) and breakpoint/orientation
+  // changes (rotate) leave it false → the sidebar switches width/position
+  // INSTANTLY there, never animating. An animated width on those events is the
+  // "sidebar opens then shrinks back by itself" flash (Bug A).
+  const [animate, setAnimate] = useState(false);
 
   useEffect(() => {
     const stored = typeof window !== 'undefined' && window.localStorage.getItem(STORAGE_KEY);
@@ -27,8 +34,35 @@ export function AppShell({ children }: { children: React.ReactNode }) {
   useEffect(() => {
     if (!hydrated) return;
     window.localStorage.setItem(STORAGE_KEY, collapsed ? '1' : '0');
+    // Keep the <html> class in lockstep with the live state so (a) the
+    // pre-paint script in layout.tsx reflects the latest choice on the NEXT
+    // refresh and (b) the pre-hydration width CSS (globals.css) never fights
+    // React once interactive — the class is removed the instant we expand.
+    document.documentElement.classList.toggle('sidebar-collapsed', collapsed);
   }, [collapsed, hydrated]);
 
+  // Turn the transition back off after an explicit toggle settles, so the next
+  // refresh / rotation / resize switches width instantly (Bug A). Re-armed by
+  // collapsed/mobileOpen so a second toggle inside the window resets the timer.
+  useEffect(() => {
+    if (!animate) return;
+    const t = window.setTimeout(() => setAnimate(false), 250);
+    return () => window.clearTimeout(t);
+  }, [animate, collapsed, mobileOpen]);
+
+  const toggleCollapse = () => {
+    setAnimate(true);
+    setCollapsed((c) => !c);
+  };
+  const openMobile = () => {
+    setAnimate(true);
+    setMobileOpen(true);
+  };
+  const closeMobile = () => {
+    setAnimate(true);
+    setMobileOpen(false);
+  };
+
   useEffect(() => {
     if (mobileOpen) {
       document.body.style.overflow = 'hidden';
@@ -44,9 +78,10 @@ export function AppShell({ children }: { children: React.ReactNode }) {
     <div className="flex min-h-screen">
       <Sidebar
         collapsed={collapsed}
-        onToggleCollapse={() => setCollapsed((c) => !c)}
+        animate={animate}
+        onToggleCollapse={toggleCollapse}
         mobileOpen={mobileOpen}
-        onMobileClose={() => setMobileOpen(false)}
+        onMobileClose={closeMobile}
       />
 
       <div className="flex min-w-0 flex-1 flex-col">
@@ -54,7 +89,7 @@ export function AppShell({ children }: { children: React.ReactNode }) {
           <button
             type="button"
             aria-label="Open navigation"
-            onClick={() => setMobileOpen(true)}
+            onClick={openMobile}
             className="inline-flex h-9 w-9 items-center justify-center rounded-sm text-slate-600 transition-colors duration-150 hover:bg-slate-100 hover:text-slate-900 dark:text-slate-400 dark:hover:bg-slate-800 dark:hover:text-slate-100 md:hidden"
           >
             <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
diff --git a/frontend/components/PriceHistoryChart.tsx b/frontend/components/PriceHistoryChart.tsx
index 985d6d55e..7e9ee4d56 100644
--- a/frontend/components/PriceHistoryChart.tsx
+++ b/frontend/components/PriceHistoryChart.tsx
@@ -1,6 +1,6 @@
 'use client';
 
-import { useEffect, useMemo, useState } from 'react';
+import { useEffect, useMemo, useRef, useState } from 'react';
 import { useTheme } from 'next-themes';
 import {
   Area,
@@ -66,31 +66,16 @@ export function PriceHistoryChart({
   // remount is how we re-assert it on those events.
   const [restKey, setRestKey] = useState(0);
   const [layoutKey, setLayoutKey] = useState(0);
+  // Chart wrapper — observed for WIDTH changes to re-park the crosshair (Bug B).
+  const wrapperRef = useRef<HTMLDivElement | null>(null);
   const { resolvedTheme } = useTheme();
 
   useEffect(() => setMounted(true), []);
 
-  // Re-park the tooltip at the latest date when the device rotates
-  // portrait↔landscape. matchMedia is browser-only; the guard keeps SSR
-  // clean (component is 'use client', so this never runs server-side).
-  // The bump is DEBOUNCED ~300ms after the orientation event so the
-  // remount lands AFTER ResponsiveContainer has re-measured the new
-  // width — remounting mid-resize makes Recharts' displayDefaultTooltip
-  // park on index 0 instead of the latest.
-  useEffect(() => {
-    if (typeof window === 'undefined') return;
-    const mq = window.matchMedia('(orientation: portrait)');
-    let t: ReturnType<typeof setTimeout>;
-    const handler = () => {
-      clearTimeout(t);
-      t = setTimeout(() => setLayoutKey((k) => k + 1), 300);
-    };
-    mq.addEventListener('change', handler);
-    return () => {
-      clearTimeout(t);
-      mq.removeEventListener('change', handler);
-    };
-  }, []);
+  // Crosshair re-park on layout change (rotation / window resize / sidebar
+  // expand-collapse) is handled by the ResizeObserver effect just below the
+  // chartData memo — a width-driven detector that subsumes the old
+  // orientation-only matchMedia listener. See that effect for the rationale.
 
   useEffect(() => {
     let cancelled = false;
@@ -153,6 +138,42 @@ export function PriceHistoryChart({
     return { abs, pct, positive: abs >= 0 };
   }, [chartData]);
 
+  // Re-park the crosshair at the latest date after any WIDTH change settles —
+  // device rotation, window resize, OR the left sidebar expanding/collapsing
+  // (which reflows the main-content width). A width change makes
+  // ResponsiveContainer re-measure the chart, but Recharts applies
+  // `defaultIndex` only on MOUNT — so without re-asserting it the crosshair
+  // drifts to a stale/left x after a re-measure (the "crosshair jumps left on
+  // sidebar toggle" bug). Bumping `layoutKey` remounts <AreaChart>, re-running
+  // displayDefaultTooltip(defaultIndex) at the latest point. DEBOUNCED ~300ms
+  // so the remount lands AFTER the re-measure — remounting mid-resize parks on
+  // index 0 (far left). The width-only delta gate ignores height-only changes
+  // so the chart's own crosshair rendering can't trigger a spurious remount.
+  // ResizeObserver is browser-only; wrapperRef is null during loading/error/
+  // empty, so the deps re-attach the observer once the chart wrapper mounts.
+  useEffect(() => {
+    const el = wrapperRef.current;
+    if (!el || typeof ResizeObserver === 'undefined') return;
+    let lastWidth = el.getBoundingClientRect().width;
+    let t: ReturnType<typeof setTimeout>;
+    const ro = new ResizeObserver((entries) => {
+      const w = entries[0].contentRect.width;
+      if (Math.abs(w - lastWidth) < 1) return; // height-only change → ignore
+      lastWidth = w;
+      clearTimeout(t);
+      t = setTimeout(() => setLayoutKey((k) => k + 1), 300);
+    });
+    ro.observe(el);
+    return () => {
+      clearTimeout(t);
+      ro.disconnect();
+    };
+    // Re-attach only when the wrapper's existence changes (loading/error/data);
+    // NOT on chartData.length — the wrapper div persists across period switches
+    // (only the inner <AreaChart> remounts via key), so the observer stays valid
+    // and a period change needn't disconnect/re-observe.
+  }, [loading, error, data]);
+
   if (loading) {
     // Skeleton placeholder — shimmer blocks roughly match the layout
     // shipped after load (current-price headline + change indicator +
@@ -467,6 +488,7 @@ export function PriceHistoryChart({
           then sized itself to and sustained; the document clip stops the
           layout viewport from ever growing. */}
       <div
+        ref={wrapperRef}
         className="h-64 w-full [&_.recharts-surface]:overflow-visible"
         style={{ touchAction: 'pan-y' }}
         onPointerDown={(e) => {
diff --git a/frontend/components/Sidebar.tsx b/frontend/components/Sidebar.tsx
index beb062a2f..caebf4c33 100644
--- a/frontend/components/Sidebar.tsx
+++ b/frontend/components/Sidebar.tsx
@@ -70,12 +70,16 @@ const RESOURCE_ITEMS: Array<{ label: string; href: string; external: true; icon:
 
 interface SidebarProps {
   collapsed: boolean;
+  /** True only for the ~250ms around an explicit user toggle — gates the
+   *  width/transform transition so refresh + rotation switch instantly
+   *  (no "opens then shrinks back" flash). Owned by AppShell. */
+  animate: boolean;
   onToggleCollapse: () => void;
   mobileOpen: boolean;
   onMobileClose: () => void;
 }
 
-export function Sidebar({ collapsed, onToggleCollapse, mobileOpen, onMobileClose }: SidebarProps) {
+export function Sidebar({ collapsed, animate, onToggleCollapse, mobileOpen, onMobileClose }: SidebarProps) {
   const pathname = usePathname() ?? '/';
 
   return (
@@ -98,7 +102,12 @@ export function Sidebar({ collapsed, onToggleCollapse, mobileOpen, onMobileClose
 
       <aside
         aria-label="Primary navigation"
-        className={`fixed inset-y-0 left-0 z-40 flex flex-col border-r border-slate-200 bg-white [transition:transform_200ms_ease-out,width_200ms_ease-out] dark:border-slate-800 dark:bg-slate-950 md:sticky md:top-0 md:h-screen md:translate-x-0 ${
+        data-sidebar-rail=""
+        className={`fixed inset-y-0 left-0 z-40 flex flex-col border-r border-slate-200 bg-white ${
+          animate
+            ? '[transition:transform_200ms_ease-out,width_200ms_ease-out]'
+            : 'transition-none'
+        } motion-reduce:transition-none dark:border-slate-800 dark:bg-slate-950 md:sticky md:top-0 md:h-screen md:translate-x-0 ${
           mobileOpen ? 'translate-x-0' : '-translate-x-full'
         } w-64 ${collapsed ? 'md:w-16 md:max-w-[64px]' : 'md:w-60 md:max-w-[240px]'}`}
       >
@@ -115,6 +124,7 @@ export function Sidebar({ collapsed, onToggleCollapse, mobileOpen, onMobileClose
             mobile drawer (< md) always shows the full horizontal row (Q +
             wordmark + close-X). */}
         <div
+          data-rail="header"
           className={`flex h-14 items-center gap-2 border-b border-slate-200 px-3 dark:border-slate-800${collapsed ? ' md:h-auto md:flex-col md:justify-center md:gap-1.5 md:px-2 md:py-3' : ''}`}
         >
           <Link
@@ -126,10 +136,11 @@ export function Sidebar({ collapsed, onToggleCollapse, mobileOpen, onMobileClose
             <span aria-hidden="true" className="inline-flex h-7 w-7 shrink-0 items-center justify-center rounded-sm bg-emerald-700 font-mono text-xs font-semibold text-white dark:bg-emerald-600 dark:text-white">Q</span>
             {/* Mobile drawer always shows the wordmark; `collapsed` is a
                 desktop-only (md+) concept, so it only hides at md+ via CSS. */}
-            <span className={`font-slab text-lg font-semibold tracking-tight${collapsed ? ' md:hidden' : ''}`}>QuantRank</span>
+            <span data-rail="hide" className={`font-slab text-lg font-semibold tracking-tight${collapsed ? ' md:hidden' : ''}`}>QuantRank</span>
           </Link>
           <button
             type="button"
+            data-rail="chevron"
             aria-label={collapsed ? 'Expand sidebar' : 'Collapse sidebar'}
             onClick={onToggleCollapse}
             className={`hidden h-8 w-8 items-center justify-center rounded-sm text-slate-500 hover:bg-slate-100 hover:text-slate-900 dark:text-slate-400 dark:hover:bg-slate-800 dark:hover:text-slate-100 md:inline-flex ${collapsed ? 'md:h-auto md:w-full md:bg-slate-100 md:py-1.5 md:dark:bg-slate-800' : 'ml-auto'}`}
@@ -203,13 +214,13 @@ export function Sidebar({ collapsed, onToggleCollapse, mobileOpen, onMobileClose
             mutually exclusive per breakpoint (the hidden one is display:none,
             so a11y sees exactly one). 2026-05-29 mobile-drawer fix. */}
         <div className="border-t border-slate-200 px-2 py-2 dark:border-slate-800">
-          <div className={collapsed ? 'md:hidden' : ''}>
+          <div data-rail="hide" className={collapsed ? 'md:hidden' : ''}>
             <ThemeToggle layout="row" />
           </div>
-          <div className={`hidden justify-center${collapsed ? ' md:flex' : ''}`}>
+          <div data-rail="show" className={`hidden justify-center${collapsed ? ' md:flex' : ''}`}>
             <ThemeToggle layout="icon" />
           </div>
-          <div className={`mt-2 px-2 pb-1 text-[0.6875rem] leading-snug text-slate-500 dark:text-slate-400${collapsed ? ' md:hidden' : ''}`}>
+          <div data-rail="hide" className={`mt-2 px-2 pb-1 text-[0.6875rem] leading-snug text-slate-500 dark:text-slate-400${collapsed ? ' md:hidden' : ''}`}>
             <p className="font-semibold uppercase tracking-[0.14em] text-slate-600 dark:text-slate-400">v1.4.0 · MIT</p>
             <p className="mt-1">Educational use only.</p>
           </div>
@@ -230,7 +241,7 @@ function SidebarSection({
 }) {
   return (
     <div className="mb-4">
-      <div className={`px-2 pb-1.5 text-[0.625rem] font-semibold uppercase tracking-[0.14em] text-slate-500 dark:text-slate-400${collapsed ? ' md:hidden' : ''}`}>
+      <div data-rail="hide" className={`px-2 pb-1.5 text-[0.625rem] font-semibold uppercase tracking-[0.14em] text-slate-500 dark:text-slate-400${collapsed ? ' md:hidden' : ''}`}>
         {label}
       </div>
       <ul className="space-y-0.5">{children}</ul>
@@ -266,7 +277,7 @@ function SidebarLink({
       <span className={`shrink-0 ${active ? 'text-slate-900 dark:text-slate-100' : 'text-slate-500 group-hover:text-slate-700 dark:text-slate-400 dark:group-hover:text-slate-200'}`}>
         {icon}
       </span>
-      <span className={`truncate${collapsed ? ' md:hidden' : ''}`}>{label}</span>
+      <span data-rail="hide" className={`truncate${collapsed ? ' md:hidden' : ''}`}>{label}</span>
       {external && (
         <svg
           width="11"
@@ -277,6 +288,7 @@ function SidebarLink({
           strokeWidth="2"
           strokeLinecap="round"
           strokeLinejoin="round"
+          data-rail="hide"
           className={`ml-auto text-slate-400 dark:text-slate-500${collapsed ? ' md:hidden' : ''}`}
           aria-hidden="true"
         >
@@ -291,11 +303,11 @@ function SidebarLink({
   return (
     <li>
       {external ? (
-        <a href={href} target="_blank" rel="noreferrer" className={base} title={collapsed ? label : undefined}>
+        <a href={href} target="_blank" rel="noreferrer" data-rail="navlink" className={base} title={collapsed ? label : undefined}>
           {content}
         </a>
       ) : (
-        <Link href={href} onClick={onClick} className={base} title={collapsed ? label : undefined}>
+        <Link href={href} onClick={onClick} data-rail="navlink" className={base} title={collapsed ? label : undefined}>
           {content}
         </Link>
       )}
diff --git a/tests/test_ingest/test_osap.py b/tests/test_ingest/test_osap.py
index 3095eafe1..4eb79decf 100644
--- a/tests/test_ingest/test_osap.py
+++ b/tests/test_ingest/test_osap.py
@@ -32,12 +32,17 @@ def test_package_imports_and_exposes_openap_class():
     larger Phase 4h integration commits to it.
     """
     assert hasattr(openassetpricing, "OpenAP")
-    # OpenAP() ctor takes optional release_year; instantiating it
-    # without args proves the default release path works without
-    # needing a network call.
-    instance = openassetpricing.OpenAP()
+    # Check the API surface on the CLASS, not an instance. Instantiating
+    # OpenAP() in openassetpricing 0.0.2 triggers a live Google-Drive metadata
+    # download inside the constructor — which made this default-lane scout test
+    # flaky whenever Drive rate-limits (the fetch returns a "Quota exceeded"
+    # HTML page and polars then raises ColumnNotFoundError on the missing
+    # "Acronym" column). The four methods are class-level defs, so hasattr
+    # resolves them without constructing an instance / hitting the network. The
+    # live instantiation + fetch path stays covered by the @network
+    # test_fetch_osap_returns_live below.
     for method in ("dl_port", "dl_signal", "dl_all_signals", "list_port"):
-        assert hasattr(instance, method), f"OpenAP missing method: {method}"
+        assert hasattr(openassetpricing.OpenAP, method), f"OpenAP missing method: {method}"
 
 
 def test_cache_hit_returns_parquet(monkeypatch, tmp_path):
diff --git a/tests/test_validation/test_ranking_history.py b/tests/test_validation/test_ranking_history.py
index 14a14066f..00110cc01 100644
--- a/tests/test_validation/test_ranking_history.py
+++ b/tests/test_validation/test_ranking_history.py
@@ -149,6 +149,17 @@ def test_load_ranking_history_smoke_recent_window() -> None:
         end_date=date(2026, 5, 27),
     )
     assert isinstance(df, pd.DataFrame)
+    if df.empty:
+        pytest.skip(
+            "Shallow git clone — no rankings.json history reachable in the "
+            "window (CI actions/checkout fetch-depth=1 default; the tip commit "
+            "may not touch rankings.json). The populated-shape assertions below "
+            "need a full clone — an empty clone legitimately yields an empty "
+            "frame. The 2-level MultiIndex on the empty frame is an "
+            "implementation detail of the empty-return path, not a contract "
+            "this test should pin; skipping keeps it from depending on it. "
+            "Mirrors the list_ranking_commits guard above + PR #284 (a820caee)."
+        )
     # Multi-index (date, ticker)
     assert df.index.nlevels == 2
     assert df.index.names == ["date", "ticker"]
