FLUTTER - DropzoneView: TargetPlatform.windows is not supported appears when hosted in firebase

Question

I was using flutter_dropzone which supports flutter web application.

When run locally the Flutter Dropzone works normally wherein I can attach file. Please see attachment

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However, when I finally hosted my flutter webapp to firebase hosting. the dropzone outputs an error "TargetPlatform.windows is not supported". Please see attachment

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commands in deploying to hosting

1. flutter build web

2. firebase deploy --only hosting:<host-name>

pubspec.yaml - enter image description here

Tried searching for related bug, the only thing that I found was that the flutter project was running in windows application.