When running Flutter web app in Chrome in debug mode, each time any settings the site had is cleared. This is because it uses a random port for each launch. To preserve settings like local storage and other site settings across debug launches use the same port.

For Visual Studio Code, add "-d", "chrome","--web-port", "8000" to args in .vscode/launch.json.

  "version": "0.2.0",
  "configurations": [
      "name": "Flutter Web Chrome (debug mode)",
      "request": "launch",
      "type": "dart",
      "program": "lib/main.dart",
      "flutterMode": "debug",
      "args": ["-d", "chrome", "--web-port", "8000"]

When running from command line, use flutter run -d chrome --web-port 8000.