@@ -192,6 +192,27 @@
   }
   #rosterReplaceBtn { border: 1px solid var(--border); background: white; }
   #rosterAddBtn { border: 1px solid var(--accent); background: var(--accent); color: white; }
+  /* An inline lead-up before the native file picker, not a silent auto-
+     trigger on the roster click itself - a system dialog appearing with
+     no warning read as a bait-and-switch ("it's in your list, but not
+     really, go find it yourself"), found by her hands-on testing. */
+  #rosterLocatePrompt {
+    border: 1px solid var(--accent);
+    background: #eef4fb;
+    border-radius: 8px;
+    padding: 0.85rem 1rem;
+    margin: 0.75rem 0;
+  }
+  #rosterLocatePrompt p { margin: 0 0 0.6rem; font-size: 0.9rem; }
+  #rosterLocatePrompt button {
+    font-size: 0.85rem;
+    padding: 0.35rem 0.75rem;
+    border-radius: 6px;
+    cursor: pointer;
+    margin-right: 0.5rem;
+  }
+  #rosterLocateConfirmBtn { border: 1px solid var(--accent); background: var(--accent); color: white; }
+  #rosterLocateCancelBtn { border: 1px solid var(--border); background: white; }
   #rosterCancelBtn { border: 1px solid var(--border); background: white; }
   #dropZone label {
     display: inline-block;
@@ -611,7 +632,10 @@
   #visitsTable { border-collapse: collapse; width: 100%; font-size: 0.9rem; }
   #visitsTable th, #visitsTable td { text-align: left; padding: 0.4rem 0.6rem; border-bottom: 1px solid var(--border); }
   #visitsTable th { color: var(--accent); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.02em; }
+  /* Same class-name collision as #eventsTable above, same fix. */
   #visitsTable tr.type-entry { background: #eaf6ee; }
+  #visitsTable tr.type-poke { background: white; }
+  #visitsTable tr.type-thigmotaxis { background: white; }
   #visitsTable tr.has-override { box-shadow: inset 3px 0 0 var(--cellflag); }
   #visitsTable .audited-badge {
     display: inline-block;
@@ -696,6 +720,13 @@ <h2>Videos</h2>
       <p class="placeholder-note" id="rosterEmptyNote">No videos yet - load one with Browse, drag/drop, or Open folder.</p>
       <ul class="roster-list" id="rosterList" hidden></ul>
       <input type="file" id="rosterLocateInput" accept="video/mp4,.mp4" hidden>
+      <div id="rosterLocatePrompt" hidden>
+        <p id="rosterLocatePromptText"></p>
+        <div>
+          <button type="button" id="rosterLocateConfirmBtn">Locate this file</button>
+          <button type="button" id="rosterLocateCancelBtn">Cancel</button>
+        </div>
+      </div>
       <button type="button" id="rosterClearBtn" hidden>Clear all videos</button>
       <div id="rosterClearConfirm" hidden>
         <p id="rosterClearConfirmText"></p>
@@ -885,10 +916,6 @@ <h2>Videos</h2>
         <canvas id="trackFailureStrip" width="640" height="24" aria-label="Tracking failure timeline: green is tracked, red is failed, across the whole video"></canvas>
       </div>
       <p class="subtitle" id="trackScrubHint" hidden>Scrub the frame viewer above - green crosshair = tracked, red X = failed frame.</p>
-
-      <p class="subtitle" id="saveProjectFileHint" hidden>Save a portable <code>_AUDITED.bmp.json</code> file with everything except the video itself (which stays wherever it already lives) - open it later, on any computer, to resume without re-tracking. Save it in the same folder as the video, next to it - the name makes it obvious at a glance, to you or anyone else, that this trial's already been done.</p>
-      <button id="saveProjectFileBtn" type="button" hidden>Save project file</button>
-      <div id="saveProjectFileStatus" role="status" aria-live="polite"></div>
     </div>
   </details>
 
@@ -954,6 +981,11 @@ <h3>Export</h3>
     </details>
     <button id="exportDetailBtn" type="button" disabled>Detect events first</button>
     <div id="exportDetailStatus" role="status" aria-live="polite"></div>
+
+    <p class="subtitle">Not spreadsheet data - a reloadable copy of this trial's own work, to resume later without re-tracking.</p>
+    <p class="subtitle" id="saveProjectFileHint" hidden>Save a portable <code>_AUDITED.bmp.json</code> file with everything except the video itself (which stays wherever it already lives) - open it later, on any computer, to resume without re-tracking. Save it in the same folder as the video, next to it - the name makes it obvious at a glance, to you or anyone else, that this trial's already been done.</p>
+    <button id="saveProjectFileBtn" type="button" hidden>Save project file</button>
+    <div id="saveProjectFileStatus" role="status" aria-live="polite"></div>
   </div>
       </div>
     </div>
@@ -1155,29 +1187,36 @@ <h3>Confirm &amp; adjust</h3>
           <button id="eventsBtn" type="button" disabled>Track mouse first</button>
           <div id="eventsStatus" role="status" aria-live="polite"></div>
 
-          <h4>Detected events</h4>
-          <div id="eventsTableWrap" hidden>
-            <table id="eventsTable">
-              <thead>
-                <tr><th>Hole</th><th>Frames</th><th>Type</th><th>Confidence</th><th>Avg speed</th><th>Human review</th><th></th></tr>
-              </thead>
-              <tbody id="eventsTableBody"></tbody>
-            </table>
+          <div class="viz-tabs" role="tablist" aria-label="Events view" id="eventsSubTabs" hidden>
+            <button type="button" role="tab" id="tab-detected-events" aria-selected="true" aria-controls="panel-detected-events">Detected events</button>
+            <button type="button" role="tab" id="tab-merged-visits" aria-selected="false" aria-controls="panel-merged-visits" tabindex="-1">Merged visits</button>
           </div>
 
-          <h4>Merged visits</h4>
-          <p class="subtitle">Two visits to the same hole count as one unless the mouse fully disengaged in between.</p>
-          <details class="info-toggle">
-            <summary>What does this mean?</summary>
-            <p class="subtitle">Two events at the same hole are merged into one visit when the raw center-density signal between them never drops close to baseline (reengage fraction x min center density) - a brief dip under the qualifying threshold doesn't end a visit, but a real return to baseline does. See DECISIONS.md 2026-09-04. Feeds the search-strategy classifier's visit sequence and the errors/perseverative-errors measure - not shown elsewhere yet.</p>
-          </details>
-          <div id="visitsTableWrap" hidden>
-            <table id="visitsTable">
-              <thead>
-                <tr><th>Hole</th><th>Frames</th><th>Events merged</th><th>Type</th><th></th></tr>
-              </thead>
-              <tbody id="visitsTableBody"></tbody>
-            </table>
+          <div role="tabpanel" id="panel-detected-events" aria-labelledby="tab-detected-events">
+            <div id="eventsTableWrap" hidden>
+              <table id="eventsTable">
+                <thead>
+                  <tr><th>Hole</th><th>Frames</th><th>Type</th><th>Confidence</th><th>Avg speed</th><th>Human review</th><th></th></tr>
+                </thead>
+                <tbody id="eventsTableBody"></tbody>
+              </table>
+            </div>
+          </div>
+
+          <div role="tabpanel" id="panel-merged-visits" aria-labelledby="tab-merged-visits" hidden>
+            <p class="subtitle">Two visits to the same hole count as one unless the mouse fully disengaged in between.</p>
+            <details class="info-toggle">
+              <summary>What does this mean?</summary>
+              <p class="subtitle">Two events at the same hole are merged into one visit when the raw center-density signal between them never drops close to baseline (reengage fraction x min center density) - a brief dip under the qualifying threshold doesn't end a visit, but a real return to baseline does. See DECISIONS.md 2026-09-04. Feeds the search-strategy classifier's visit sequence and the errors/perseverative-errors measure - not shown elsewhere yet.</p>
+            </details>
+            <div id="visitsTableWrap" hidden>
+              <table id="visitsTable">
+                <thead>
+                  <tr><th>Hole</th><th>Frames</th><th>Events merged</th><th>Type</th><th></th></tr>
+                </thead>
+                <tbody id="visitsTableBody"></tbody>
+              </table>
+            </div>
           </div>
         </div>
       </details>
 
@@ -133,6 +133,10 @@ const rosterCancelBtn = document.getElementById('rosterCancelBtn');
 const rosterListEl = document.getElementById('rosterList');
 const rosterEmptyNoteEl = document.getElementById('rosterEmptyNote');
 const rosterLocateInput = document.getElementById('rosterLocateInput');
+const rosterLocatePrompt = document.getElementById('rosterLocatePrompt');
+const rosterLocatePromptText = document.getElementById('rosterLocatePromptText');
+const rosterLocateConfirmBtn = document.getElementById('rosterLocateConfirmBtn');
+const rosterLocateCancelBtn = document.getElementById('rosterLocateCancelBtn');
 const rosterClearBtn = document.getElementById('rosterClearBtn');
 const rosterClearConfirm = document.getElementById('rosterClearConfirm');
 const rosterClearConfirmText = document.getElementById('rosterClearConfirmText');
@@ -250,24 +254,42 @@ async function renderRosterList() {
 
 async function handleRosterClick(key, fileName) {
     if (key === currentVideoKey || inputLocked) return;
+    // Clicking any roster row dismisses a stale locate-prompt left over
+    // from a previous attempt at a different (or the same) video.
+    rosterLocateKey = null;
+    rosterLocatePrompt.hidden = true;
     const file = await resolveFileForKey(key);
     if (file) {
         await loadVideoOrSwitch(file);
         return;
     }
     // Only reachable for a video an Open folder/Select videos pick named
     // but that was never actually loaded in any session - nothing to
-    // recover, so ask for it back rather than silently doing nothing.
+    // recover. Shows an inline prompt with its own button rather than
+    // firing the native file picker straight from this click - a system
+    // dialog appearing with no lead-up read as "it's in your list, but
+    // not really, go find it yourself," found by hands-on testing.
     rosterLocateKey = key;
-    setStatus(`Locate ${fileName} to switch to it - it hasn't been opened yet, so there's no saved copy to switch to instantly.`, 'info');
-    rosterLocateInput.click();
+    rosterLocatePromptText.textContent =
+        `"${fileName}" hasn't been opened yet, so there's no saved copy to switch to instantly - locate it on your computer to open it.`;
+    rosterLocatePrompt.hidden = false;
 }
 
+rosterLocateConfirmBtn.addEventListener('click', () => {
+    rosterLocateInput.click();
+});
+
+rosterLocateCancelBtn.addEventListener('click', () => {
+    rosterLocateKey = null;
+    rosterLocatePrompt.hidden = true;
+});
+
 rosterLocateInput.addEventListener('change', async () => {
     const picked = rosterLocateInput.files[0];
     rosterLocateInput.value = '';
     const key = rosterLocateKey;
     rosterLocateKey = null;
+    rosterLocatePrompt.hidden = true;
     if (!picked || !key) return;
     if (videoKeyFor(picked) !== key) {
         setStatus(`That file's name/size/modified-date don't match what was recorded for this entry - pick the original file.`, 'error');
@@ -286,9 +308,11 @@ rosterClearBtn.addEventListener('click', async () => {
         return;
     }
     rosterClearConfirmText.textContent =
-        `Remove all ${entries.length} video${entries.length === 1 ? '' : 's'} from this list and delete ` +
-        `their saved ROI/tracking work${currentVideoKey ? ' - including whatever is open right now' : ''}? ` +
-        `This cannot be undone; your original video files on disk are untouched.`;
+        `Before you clear this out - if there's a video here you want to keep, save its project file first ` +
+        `(look for "Save project file" once it's tracked; it downloads as an easy-to-spot "..._AUDITED.bmp.json" ` +
+        `file you can keep next to the video). Clearing removes ${entries.length} video${entries.length === 1 ? '' : 's'} ` +
+        `from this list and their saved ROI/tracking work${currentVideoKey ? ", including whatever's open right now" : ''}. ` +
+        `Your original video files on disk are safe either way.`;
     rosterClearBtn.hidden = true;
     rosterClearConfirm.hidden = false;
 });
@@ -964,6 +988,52 @@ const eventsTableWrap = document.getElementById('eventsTableWrap');
 const eventsTableBody = document.getElementById('eventsTableBody');
 const visitsTableWrap = document.getElementById('visitsTableWrap');
 const visitsTableBody = document.getElementById('visitsTableBody');
+const eventsSubTabs = document.getElementById('eventsSubTabs');
+const tabDetectedEvents = document.getElementById('tab-detected-events');
+const tabMergedVisits = document.getElementById('tab-merged-visits');
+const panelDetectedEvents = document.getElementById('panel-detected-events');
+const panelMergedVisits = document.getElementById('panel-merged-visits');
+
+// Detected events / Merged visits as two tabs, not two stacked full-page
+// tables - a real trial can produce well over a thousand raw event rows
+// before merging, and scrolling past all of them to reach the (usually
+// much shorter) merged table was the actual complaint. Same real ARIA
+// tablist mechanism as the Video/Path/Heat map/Raster tabs above (not a
+// new pattern) - deliberately a separate small table rather than
+// generalizing VIZ_TABS, since this pair has no per-tab onActivate work.
+const EVENTS_SUB_TABS = [
+    { tab: tabDetectedEvents, panel: panelDetectedEvents },
+    { tab: tabMergedVisits, panel: panelMergedVisits },
+];
+
+function activateEventsSubTab(target) {
+    for (const { tab, panel } of EVENTS_SUB_TABS) {
+        const active = tab === target;
+        tab.setAttribute('aria-selected', active ? 'true' : 'false');
+        tab.tabIndex = active ? 0 : -1;
+        panel.hidden = !active;
+    }
+}
+
+for (const { tab } of EVENTS_SUB_TABS) {
+    tab.addEventListener('click', () => activateEventsSubTab(tab));
+}
+
+eventsSubTabs.addEventListener('keydown', (e) => {
+    if (!['ArrowLeft', 'ArrowRight', 'Home', 'End'].includes(e.key)) return;
+    const tabs = EVENTS_SUB_TABS.map((v) => v.tab);
+    const currentIndex = tabs.indexOf(document.activeElement);
+    if (currentIndex === -1) return;
+    let nextIndex;
+    if (e.key === 'ArrowLeft') nextIndex = (currentIndex - 1 + tabs.length) % tabs.length;
+    else if (e.key === 'ArrowRight') nextIndex = (currentIndex + 1) % tabs.length;
+    else if (e.key === 'Home') nextIndex = 0;
+    else nextIndex = tabs.length - 1;
+    const next = tabs[nextIndex];
+    next.focus();
+    activateEventsSubTab(next);
+    e.preventDefault();
+});
 const measuresBtn = document.getElementById('measuresBtn');
 const measuresStatusEl = document.getElementById('measuresStatus');
 const measuresTableWrap = document.getElementById('measuresTableWrap');
@@ -1779,6 +1849,7 @@ async function loadVideo(file, { isResume = false, keepLocked = false } = {}) {
     trackStatusEl.textContent = '';
     eventsSection.hidden = true;
     eventsQcSection.hidden = true;
+    eventsSubTabs.hidden = true;
     eventsTableWrap.hidden = true;
     visitsTableWrap.hidden = true;
     eventsStatusEl.textContent = '';
@@ -2762,6 +2833,10 @@ function runEventDetection() {
         const visits = mergeVisits(events, trackResult.holeSignals.centerDensity, { minCenterDensity, reengageFraction });
         renderVisitsTable(visits);
         visitsTableWrap.hidden = visits.length === 0;
+        // The tab pair only makes sense once there's something to switch
+        // between - stays hidden (from the reset block above) if this
+        // trial produced nothing on either side.
+        eventsSubTabs.hidden = events.length === 0 && visits.length === 0;
 
         currentVisits = visits;
         tabRaster.disabled = false;