fix: skip node metadata paste when media node is selected (#9773)

## Summary

- When a media node (LoadImage/LoadAudio/LoadVideo) is selected and the
clipboard contains stale node metadata from a prior Ctrl+C, pasting
skips the node-metadata deserialization so that the paste falls through
to litegraph's default handler instead of incorrectly pasting the old
copied node.
- Fixes Comfy-Org/ComfyUI#12896

## Root Cause

The paste handler in `usePaste.ts` checks clipboard `text/html` for
`data-metadata` (serialized node data) **before** falling through to
litegraph's default paste. When a user copies a node, then copies a web
image, the browser clipboard may retain the old `data-metadata` in
`text/html` while the image data is not available as a
`DataTransferItem` file. This causes the stale node to be pasted instead
of the image.

## Fix

Skip `pasteClipboardItems()` when a media node is selected, allowing the
paste to fall through to litegraph's default handler which can handle
the clipboard content appropriately.

## Test plan

- [x] Added unit test verifying node metadata paste is skipped when
media node is selected
- [x] Manual: Copy a node → copy a web image → select LoadImage node →
Ctrl+V → verify image is pasted, not the node


## AS IS 


https://github.com/user-attachments/assets/210d77d3-5c49-4e38-91b7-b9d9ea0e7ca0



## TO BE



https://github.com/user-attachments/assets/b68e4582-0c57-48b8-9ed9-0b3243bb1554




🤖 Generated with [Claude Code](https://claude.com/claude-code)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9773-fix-skip-node-metadata-paste-when-media-node-is-selected-3216d73d3650814d92dadcd0c0ec79c7)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: GitHub Action <action@github.com>

browser_tests/assets/nodes/load_image_with_ksampler.json

@@ -0,0 +1,47 @@
+{
+  "last_node_id": 2,
+  "last_link_id": 0,
+  "nodes": [
+    {
+      "id": 1,
+      "type": "LoadImage",
+      "pos": [50, 50],
+      "size": [315, 314],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [],
+      "outputs": [
+        { "name": "IMAGE", "type": "IMAGE", "links": null },
+        { "name": "MASK", "type": "MASK", "links": null }
+      ],
+      "properties": { "Node name for S&R": "LoadImage" },
+      "widgets_values": ["example.png", "image"]
+    },
+    {
+      "id": 2,
+      "type": "KSampler",
+      "pos": [500, 50],
+      "size": [315, 262],
+      "flags": {},
+      "order": 1,
+      "mode": 0,
+      "inputs": [
+        { "name": "model", "type": "MODEL", "link": null },
+        { "name": "positive", "type": "CONDITIONING", "link": null },
+        { "name": "negative", "type": "CONDITIONING", "link": null },
+        { "name": "latent_image", "type": "LATENT", "link": null }
+      ],
+      "outputs": [{ "name": "LATENT", "type": "LATENT", "links": null }],
+      "properties": { "Node name for S&R": "KSampler" },
+      "widgets_values": [0, "randomize", 20, 8, "euler", "normal", 1]
+    }
+  ],
+  "links": [],
+  "groups": [],
+  "config": {},
+  "extra": {
+    "ds": { "offset": [0, 0], "scale": 1 }
+  },
+  "version": 0.4
+}

browser_tests/tests/imagePastePriority.spec.ts

@@ -0,0 +1,58 @@
+import { expect } from '@playwright/test'
+
+import { comfyPageFixture as test } from '../fixtures/ComfyPage'
+
+test.describe(
+  'Image paste priority over stale node metadata',
+  { tag: ['@node'] },
+  () => {
+    test('Should not paste copied node when a LoadImage node is selected and clipboard has stale node metadata', async ({
+      comfyPage
+    }) => {
+      await comfyPage.workflow.loadWorkflow('nodes/load_image_with_ksampler')
+
+      const initialCount = await comfyPage.nodeOps.getGraphNodesCount()
+      expect(initialCount).toBe(2)
+
+      // Copy the KSampler node (puts data-metadata in clipboard)
+      const ksamplerNodes =
+        await comfyPage.nodeOps.getNodeRefsByType('KSampler')
+      await ksamplerNodes[0].copy()
+
+      // Select the LoadImage node
+      const loadImageNodes =
+        await comfyPage.nodeOps.getNodeRefsByType('LoadImage')
+      await loadImageNodes[0].click('title')
+
+      // Simulate pasting when clipboard has stale node metadata (text/html
+      // with data-metadata) but no image file items. This replicates the bug
+      // scenario: user copied a node, then copied a web image (which replaces
+      // clipboard files but may leave stale text/html with node metadata).
+      await comfyPage.page.evaluate(() => {
+        const nodeData = { nodes: [{ type: 'KSampler', id: 99 }] }
+        const base64 = btoa(JSON.stringify(nodeData))
+        const html =
+          '<meta charset="utf-8"><div><span data-metadata="' +
+          base64 +
+          '"></span></div><span style="white-space:pre-wrap;">Text</span>'
+
+        const dataTransfer = new DataTransfer()
+        dataTransfer.setData('text/html', html)
+
+        const event = new ClipboardEvent('paste', {
+          clipboardData: dataTransfer,
+          bubbles: true,
+          cancelable: true
+        })
+        document.dispatchEvent(event)
+      })
+
+      await comfyPage.nextFrame()
+
+      // Node count should remain the same — stale node metadata should NOT
+      // be deserialized when a media node is selected.
+      const finalCount = await comfyPage.nodeOps.getGraphNodesCount()
+      expect(finalCount).toBe(initialCount)
+    })
+  }
+)

src/composables/usePaste.test.ts

@@ -595,6 +595,34 @@ describe('usePaste', () => {
       )
     })
   })
+
+  it('should skip node metadata paste when a media node is selected', async () => {
+    const mockNode = createMockLGraphNode({
+      is_selected: true,
+      pasteFile: vi.fn(),
+      pasteFiles: vi.fn()
+    })
+    mockCanvas.current_node = mockNode
+    vi.mocked(isImageNode).mockReturnValue(true)
+
+    usePaste()
+
+    const nodeData = { nodes: [{ type: 'KSampler' }] }
+    const encoded = btoa(JSON.stringify(nodeData))
+    const html = `<div data-metadata="${encoded}"></div>`
+
+    const dataTransfer = new DataTransfer()
+    dataTransfer.setData('text/html', html)
+    dataTransfer.setData('text/plain', 'some text')
+
+    const event = new ClipboardEvent('paste', { clipboardData: dataTransfer })
+    document.dispatchEvent(event)
+
+    await vi.waitFor(() => {
+      expect(mockCanvas._deserializeItems).not.toHaveBeenCalled()
+      expect(mockCanvas.pasteFromClipboard).toHaveBeenCalled()
+    })
+  })
 })
 
 describe('cloneDataTransfer', () => {

src/composables/usePaste.ts

@@ -229,7 +229,10 @@ export const usePaste = () => {
         return
       }
     }
-    if (pasteClipboardItems(data)) return
+
+    const isMediaNodeSelected =
+      isImageNodeSelected || isVideoNodeSelected || isAudioNodeSelected
+    if (!isMediaNodeSelected && pasteClipboardItems(data)) return
 
     // No image found. Look for node data
     data = data.getData('text/plain')