fix(desktop): dedupe clipboard image paste

apps/desktop/src/app/chat/composer/text-utils.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { detectTrigger } from './text-utils'
+import { blobDedupeKey, detectTrigger, extractClipboardImageBlobs } from './text-utils'
 
 describe('detectTrigger', () => {
   it('detects a bare slash trigger with an empty query', () => {
@@ -23,3 +23,55 @@ describe('detectTrigger', () => {
     expect(detectTrigger('hello there')).toBeNull()
   })
 })
+
+describe('extractClipboardImageBlobs', () => {
+  it('dedupes the same image exposed on both items and files', () => {
+    const image = new File([new Uint8Array([1, 2, 3])], 'paste.png', {
+      type: 'image/png',
+      lastModified: 1_700_000_000_000
+    })
+
+    const clipboard = {
+      files: {
+        length: 1,
+        item: (index: number) => (index === 0 ? image : null)
+      },
+      getData: () => '',
+      items: [
+        {
+          kind: 'file',
+          type: 'image/png',
+          getAsFile: () => image
+        }
+      ]
+    } as unknown as DataTransfer
+
+    expect(extractClipboardImageBlobs(clipboard)).toEqual([image])
+  })
+
+  it('falls back to files when items has no image', () => {
+    const image = new File([new Uint8Array([4, 5])], 'shot.jpg', {
+      type: 'image/jpeg',
+      lastModified: 1_700_000_000_001
+    })
+
+    const clipboard = {
+      files: {
+        length: 1,
+        item: (index: number) => (index === 0 ? image : null)
+      },
+      getData: () => '',
+      items: []
+    } as unknown as DataTransfer
+
+    expect(extractClipboardImageBlobs(clipboard)).toEqual([image])
+  })
+})
+
+describe('blobDedupeKey', () => {
+  it('uses file metadata for File blobs', () => {
+    const file = new File([], 'a.png', { type: 'image/png', lastModified: 42 })
+
+    expect(blobDedupeKey(file)).toBe('file:a.png:0:image/png:42')
+  })
+})

apps/desktop/src/app/chat/composer/text-utils.ts

@@ -8,16 +8,31 @@ export interface TriggerState {
 
 const TRIGGER_RE = /(?:^|[\s])([@/])([^\s@/]*)$/
 
+/** Stable key for paste dedupe — `items` and `files` often mirror the same image as different objects. */
+export function blobDedupeKey(blob: Blob): string {
+  if (blob instanceof File) {
+    return `file:${blob.name}:${blob.size}:${blob.type}:${blob.lastModified}`
+  }
+
+  return `blob:${blob.size}:${blob.type}`
+}
+
 export function extractClipboardImageBlobs(clipboard: DataTransfer): Blob[] {
   const blobs: Blob[] = []
-  const seen = new Set<Blob>()
+  const seen = new Set<string>()
 
   const push = (blob: Blob | null) => {
-    if (!blob || blob.size === 0 || seen.has(blob)) {
+    if (!blob || blob.size === 0) {
+      return
+    }
+
+    const key = blobDedupeKey(blob)
+
+    if (seen.has(key)) {
       return
     }
 
-    seen.add(blob)
+    seen.add(key)
     blobs.push(blob)
   }
 
@@ -29,7 +44,8 @@ export function extractClipboardImageBlobs(clipboard: DataTransfer): Blob[] {
     }
   }
 
-  if (clipboard.files?.length) {
+  // Chromium/Electron expose the same pasted image on both `items` and `files`.
+  if (blobs.length === 0 && clipboard.files?.length) {
     for (let i = 0; i < clipboard.files.length; i += 1) {
       const file = clipboard.files.item(i)