Problem here is FFUploadedFile type. It's a variation of File type created specifically for Flutterflow. However, it happens to have some weird limitation compared to original flutter version.

I had similar code using file from dart.io package, so to test this I added localFile, fileFF and bytesFF to check how it will work with FFUploadedFile:

import 'dart:io';\nimport 'package:flutter/services.dart';\nimport 'package:mime/mime.dart';\n\nFuture<FFUploadedFile?> readMediaFromStorage(\n  String localPath,\n  FFUploadedFile? localFile,\n) async {\n  try {\n    final file = File(localPath);\n    final fileFF = localFile;\n\n    if (await file.exists()) {\n      final bytes = await file.readAsBytes();\n      final bytesFF = await fileFF!.readAsBytes();\n\n      final fileName = file.path.split('/').last;\n      final mimeType = lookupMimeType(file.path) ?? 'application/octet-stream';\n\n      return FFUploadedFile(\n        name: fileName,\n        bytes: bytes,\n        width: 360.0, // Set the width\n        height: 360.0, // Set the height\n        blurHash: null,\n      );\n    } else {\n      return null; // Return null if the file does not exist\n    }\n  } catch (e) {\n    print('Error reading file from storage: $e');\n    return null; // Return null if an error occurs\n  }\n}

Result? Same as yours.

So I would suggest replacing FFUploadedFile with classic file to work on

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