Put Duplicate on the drawings list; do not require a time under the click.

The handler never ran — no event, no POST. Right-click in empty time
also hid the menu. List button uses the selected trendline.

static/app.js

@@ -1112,6 +1112,23 @@ createApp({
       return `${base} ${number}`;
     }
 
+    const selectedTrendline = computed(() => {
+      const id = selectedDrawing.value;
+      if (!id) return null;
+      const line = levels.value.find(level => level.id === id);
+      if (!line || line.kind !== 'manual' || !line.slope) return null;
+      return line;
+    });
+
+    async function duplicateSelected() {
+      const line = selectedTrendline.value;
+      if (!line) {
+        addEvent('DUPLICATE FAILED · select one trendline', 'error');
+        return;
+      }
+      await duplicateLine(line);
+    }
+
     async function duplicateLine(line) {
       const fail = reason => {
         addEvent(`DUPLICATE #${line.number} FAILED · ${reason}`, 'error');
@@ -1125,6 +1142,15 @@ createApp({
           }),
         }).catch(() => {});
       };
+      fetch('/api/debug/snap', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({
+          kind: 'duplicate',
+          tf: line.tf,
+          note: `start #${line.number} last_t ${line.last_t} cutoff ${line.cutoff_t}`,
+        }),
+      }).catch(() => {});
       if (line.geometry_resolved === false) {
         fail('no source geometry');
         return;
@@ -1656,6 +1682,6 @@ createApp({
       window.removeEventListener('keydown', handleKeydown);
     });
 
-    return { status, price, sessionOpen, quoteChange, animateCurrentPrice, autoScrollLivePrice, extraDetail, hideLowerTfDrawings, confluenceAlerts, barAge, dataUpdatedAt, buildStamp, timeframe, timeframes, drawingColors, drawingColorRows, drawingColorName, colorRowLabels, symbolChoices, selectedSymbol, symbolColor, symbolScale, symbolScales, symbolPanelOpen, prefs, clusters, clustersByPrice, events, eventsMore, loadOlderEvents, diagnosticMode, captureBusy, captureCountdown, captureDiagnostic, armedTool, drawName, drawColor, drawWidth, drawSide, snap, selectedDrawing, selectedDrawings, drawingList, startDrawingListResize, manualLines, hasDrawingSelection, allShownSelected, selectedAreHidden, alertPrice, alertNote, alertEarlyPoints, levelColor, levelWidth, addPriceAlert, armTool, selectTimeframe, allEnabled, toggleGroup, maValue, maAlertOn, toggleMaAlert, deleteSelected, deleteLine, toggleDrawingSelection, activateDrawing, toggleSelectAll, toggleSelectedVisibility, renameLine, updateLineStyle, updateLevelNumber, setArmed, commentText, commentFloat, comments, drawings, filteredDrawings, drawingFilter, drawingKind, drawingTf, deleteDrawing, toggleComment, togglePinned, chooseSymbol, toggleSymbolPanel, startSymbolDrag, dropSymbol, optionExpirations, optionExpiryId, optionSide, optionMode, optionMin, optionMax, optionContracts, optionUnderlying, optionBusy, optionError, optionSearched, optionCopied, onOptionsToggle, searchOptions, copyOption, canUndo, undoTitle, undo };
+    return { status, price, sessionOpen, quoteChange, animateCurrentPrice, autoScrollLivePrice, extraDetail, hideLowerTfDrawings, confluenceAlerts, barAge, dataUpdatedAt, buildStamp, timeframe, timeframes, drawingColors, drawingColorRows, drawingColorName, colorRowLabels, symbolChoices, selectedSymbol, symbolColor, symbolScale, symbolScales, symbolPanelOpen, prefs, clusters, clustersByPrice, events, eventsMore, loadOlderEvents, diagnosticMode, captureBusy, captureCountdown, captureDiagnostic, armedTool, drawName, drawColor, drawWidth, drawSide, snap, selectedDrawing, selectedDrawings, drawingList, startDrawingListResize, manualLines, hasDrawingSelection, allShownSelected, selectedAreHidden, selectedTrendline, duplicateSelected, alertPrice, alertNote, alertEarlyPoints, levelColor, levelWidth, addPriceAlert, armTool, selectTimeframe, allEnabled, toggleGroup, maValue, maAlertOn, toggleMaAlert, deleteSelected, deleteLine, toggleDrawingSelection, activateDrawing, toggleSelectAll, toggleSelectedVisibility, renameLine, updateLineStyle, updateLevelNumber, setArmed, commentText, commentFloat, comments, drawings, filteredDrawings, drawingFilter, drawingKind, drawingTf, deleteDrawing, toggleComment, togglePinned, chooseSymbol, toggleSymbolPanel, startSymbolDrag, dropSymbol, optionExpirations, optionExpiryId, optionSide, optionMode, optionMin, optionMax, optionContracts, optionUnderlying, optionBusy, optionError, optionSearched, optionCopied, onOptionsToggle, searchOptions, copyOption, canUndo, undoTitle, undo };
   },
 }).mount('#app');

static/chart.js

@@ -569,7 +569,8 @@ class ConfluenceChart {
     duplicate.textContent = 'Duplicate';
     duplicate.addEventListener('click', event => {
       event.stopPropagation();
-      const level = this.levels.find(value => value.id === this.contextLineId);
+      const id = this.contextLineId || this.selectedLineId;
+      const level = this.levels.find(value => value.id === id);
       this.hideContextMenu();
       if (level && this.onLineDuplicate) this.onLineDuplicate({ ...level });
     });
@@ -3167,9 +3168,9 @@ class ConfluenceChart {
     if (!level || !this.bars.length) return;
     event.preventDefault();
     const point = this.eventPoint(event);
-    if (!point || !this.withinPlot(point) || point.t == null) return;
+    if (!point || !this.withinPlot(point)) return;
     const lastBar = this.bars[this.bars.length - 1];
-    const cutoff = point.t > lastBar.t
+    const cutoff = point.t == null ? null : point.t > lastBar.t
       ? Math.round(point.t)
       : this.bars.reduce((nearest, bar) =>
         Math.abs(bar.t - point.t) < Math.abs(nearest.t - point.t) ? bar : nearest

static/index.html

@@ -282,6 +282,7 @@
               <i :class="selectedAreHidden ? 'fa-solid fa-eye' : 'fa-solid fa-eye-slash'"></i>
               {{ selectedAreHidden ? 'Show' : 'Hide' }}
             </button>
+            <button @click="duplicateSelected" :disabled="!selectedTrendline" aria-label="Duplicate selected trendline">Duplicate</button>
             <button @click="deleteSelected" :disabled="!selectedDrawings.length" aria-label="Delete selected drawings">Delete</button>
           </div>
           <div class="drawing-list-shell">