Update app.py

app.py

@@ -608,7 +608,7 @@ HTML_CONTENT = """
 
         uploadForm.addEventListener('submit', (e) => {
             e.preventDefault();
-            const filesToUpload = fileInput.files.length > 0 ? fileInput.files : pastedFiles;
+            const filesToUpload = fileInput.files.length > 0 ? Array.from(fileInput.files) : pastedFiles;
             if (filesToUpload.length > 0) {
                 uploadFiles(filesToUpload);
             }