From 98fb2a800929fe692f5a99a8ac7f9a289c408f57 Mon Sep 17 00:00:00 2001
From: Nick the Sick <computers@nickthesick.com>
Date: Tue, 13 Jan 2026 11:23:12 +0100
Subject: [PATCH 1/2] fix: ignore drag & drop from unrelated events #1968

---
 .../core/src/extensions/SideMenu/SideMenu.ts    | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/packages/core/src/extensions/SideMenu/SideMenu.ts b/packages/core/src/extensions/SideMenu/SideMenu.ts
index 769e4a1715..26cad4e3bf 100644
--- a/packages/core/src/extensions/SideMenu/SideMenu.ts
+++ b/packages/core/src/extensions/SideMenu/SideMenu.ts
@@ -419,6 +419,23 @@ export class SideMenuView<
    *  - Whether the drop event is within the bounds of the current editor instance
    */
   getDragEventContext = (event: DragEvent) => {
+    // Relevance gate: Only handle drags that belong to BlockNote
+    // Check if at least one of the following is true:
+    // 1. ProseMirror drag started in an editor
+    // 2. Side menu drag
+    // 3. BlockNote-specific data type in the drag
+    // 4. (optional stricter mode) Event target is inside this editor
+    const isBlockNoteDrag =
+      this.pmView.dragging !== null ||
+      this.isDragOrigin ||
+      event.dataTransfer?.types.includes("blocknote/html") ||
+      (event.target instanceof Node && this.pmView.dom.contains(event.target));
+
+    if (!isBlockNoteDrag) {
+      // Not a BlockNote-related drag, return early
+      return undefined;
+    }
+
     // We need to check if there is text content that is being dragged (select some text & just drag it)
     const textContentIsBeingDragged =
       !event.dataTransfer?.types.includes("blocknote/html") &&

From 65c8a4d38a3b69a8383a9609f85e62f5b7865b62 Mon Sep 17 00:00:00 2001
From: Nick the Sick <computers@nickthesick.com>
Date: Tue, 13 Jan 2026 15:29:54 +0100
Subject: [PATCH 2/2] fix: add more checks in other handlers

---
 .../core/src/extensions/SideMenu/SideMenu.ts  | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/packages/core/src/extensions/SideMenu/SideMenu.ts b/packages/core/src/extensions/SideMenu/SideMenu.ts
index 26cad4e3bf..e65d4b1d99 100644
--- a/packages/core/src/extensions/SideMenu/SideMenu.ts
+++ b/packages/core/src/extensions/SideMenu/SideMenu.ts
@@ -380,6 +380,20 @@ export class SideMenuView<
       return;
     }
 
+    // Relevance gate: Only handle drags that belong to BlockNote
+    // This prevents interference with external drag-and-drop libraries
+    // by avoiding calls to closeDropCursor() for non-BlockNote drags
+    const isBlockNoteDrag =
+      this.pmView.dragging !== null ||
+      this.isDragOrigin ||
+      event.dataTransfer?.types.includes("blocknote/html") ||
+      (event.target instanceof Node && this.pmView.dom.contains(event.target));
+
+    if (!isBlockNoteDrag) {
+      // Not a BlockNote-related drag, return early without any processing
+      return;
+    }
+
     const dragEventContext = this.getDragEventContext(event);
 
     if (!dragEventContext || !dragEventContext.isDropPoint) {
@@ -494,6 +508,19 @@ export class SideMenuView<
       return;
     }
 
+    // Relevance gate: Only handle drags that belong to BlockNote
+    // This prevents interference with external drag-and-drop libraries
+    const isBlockNoteDrag =
+      this.pmView.dragging !== null ||
+      this.isDragOrigin ||
+      event.dataTransfer?.types.includes("blocknote/html") ||
+      (event.target instanceof Node && this.pmView.dom.contains(event.target));
+
+    if (!isBlockNoteDrag) {
+      // Not a BlockNote-related drag, return early without any processing
+      return;
+    }
+
     const context = this.getDragEventContext(event);
     if (!context) {
       this.closeDropCursor();