Stop ghost extension clips and recover last-frame extract after an interrupt.

Only one Comfy finish path can save a clip, hide catalog entries whose MP4 is missing, and retry last-frame extract so a truncated file does not dump FFmpeg noise into the UI.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/utils/ffmpeg.ts

@@ -63,18 +63,30 @@ export async function extractLastFrame(inputPath: string, outputPath: string) {
   if (!existsSync(inputPath)) {
     throw new Error('Source video is missing')
   }
-  await runFfmpeg([
-    '-y',
-    '-sseof', '-1',
-    '-i', inputPath,
-    '-update', '1',
-    '-frames:v', '1',
-    '-q:v', '1',
-    outputPath
-  ], 30000)
-  if (!existsSync(outputPath)) {
-    throw new Error('FFmpeg did not write the last frame')
+
+  const attempts: string[][] = []
+  try {
+    const duration = await probeDuration(inputPath)
+    const seek = Math.max(0, duration - 0.08)
+    attempts.push(['-y', '-ss', seek.toFixed(3), '-i', inputPath, '-frames:v', '1', '-an', '-q:v', '1', outputPath])
+  } catch {
+    // Truncated files often have no duration index; fall through to decode attempts.
   }
+  attempts.push(
+    ['-y', '-sseof', '-0.04', '-i', inputPath, '-update', '1', '-frames:v', '1', '-an', '-q:v', '1', outputPath],
+    ['-y', '-i', inputPath, '-update', '1', '-an', '-q:v', '1', outputPath]
+  )
+
+  for (const args of attempts) {
+    try {
+      await runFfmpeg(args, 60000)
+      if (existsSync(outputPath)) return
+    } catch {
+      // Try the next seek strategy.
+    }
+  }
+
+  throw new Error('Could not extract the last frame. The video looks incomplete — interrupting Comfy mid-encode usually causes this. Earlier saved parts are still in the library.')
 }
 
 export async function probeHasAudio(filePath: string) {