diff --git a/static/chart.js b/static/chart.js
index 0913190..b428759 100644
--- a/static/chart.js
+++ b/static/chart.js
@@ -567,7 +567,8 @@ class ConfluenceChart {
     duplicate.type = 'button';
     duplicate.dataset.action = 'duplicate';
     duplicate.textContent = 'Duplicate';
-    duplicate.addEventListener('click', event => {
+    duplicate.addEventListener('pointerdown', event => {
+      event.preventDefault();
       event.stopPropagation();
       const id = this.contextLineId || this.selectedLineId;
       const level = this.levels.find(value => value.id === id);
@@ -584,6 +585,7 @@ class ConfluenceChart {
       this.hideContextMenu();
       if (id && this.onLineDelete) this.onLineDelete(id);
     });
+    this.contextMenu.addEventListener('pointerdown', event => event.stopPropagation());
     this.contextMenu.addEventListener('click', event => event.stopPropagation());
     this.contextMenu.append(endHere, extend, duplicate, deleteLine);
     this.overlayLayer.appendChild(this.contextMenu);