[fix] Restore ability to override onMouseDown in node subclasses

src/lib/litegraph/src/LGraphCanvas.ts

@@ -2683,6 +2683,26 @@ export class LGraphCanvas
         this.processNodeDblClicked(node)
       }
 
+      // Check for title button clicks before calling onMouseDown
+      if (node.title_buttons?.length && !node.flags.collapsed) {
+        // pos contains the offset from the node's position, so we need to use node-relative coordinates
+        const nodeRelativeX = pos[0]
+        const nodeRelativeY = pos[1]
+
+        for (let i = 0; i < node.title_buttons.length; i++) {
+          const button = node.title_buttons[i]
+          if (
+            button.visible &&
+            button.isPointInside(nodeRelativeX, nodeRelativeY)
+          ) {
+            node.onTitleButtonClick(button, this)
+            // Set a no-op click handler to prevent fallback canvas dragging
+            pointer.onClick = () => {}
+            return
+          }
+        }
+      }
+
       // Mousedown callback - can block drag
       if (node.onMouseDown?.(e, pos, this)) {
         // Node handled the event (e.g., title button clicked)

src/lib/litegraph/src/LGraphNode.ts

@@ -728,34 +728,6 @@ export class LGraphNode
       error: this.#getErrorStrokeStyle,
       selected: this.#getSelectedStrokeStyle
     }
-
-    // Assign onMouseDown implementation
-    this.onMouseDown = (
-      // @ts-expect-error - CanvasPointerEvent type needs fixing
-      e: CanvasPointerEvent,
-      pos: Point,
-      canvas: LGraphCanvas
-    ): boolean => {
-      // Check for title button clicks (only if not collapsed)
-      if (this.title_buttons?.length && !this.flags.collapsed) {
-        // pos contains the offset from the node's position, so we need to use node-relative coordinates
-        const nodeRelativeX = pos[0]
-        const nodeRelativeY = pos[1]
-
-        for (let i = 0; i < this.title_buttons.length; i++) {
-          const button = this.title_buttons[i]
-          if (
-            button.visible &&
-            button.isPointInside(nodeRelativeX, nodeRelativeY)
-          ) {
-            this.onTitleButtonClick(button, canvas)
-            return true // Prevent default behavior
-          }
-        }
-      }
-
-      return false // Allow default behavior
-    }
   }
 
   /** Internal callback for subgraph nodes. Do not implement externally. */