Non-fatal Exception: io.flutter.plugins.firebase.crashlytics.FlutterError: Null check operator used on a null value. Error thrown Instance of 'ErrorDescription'. about open-mail-app-flutter HOT 1 OPEN

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Non-fatal Exception: io.flutter.plugins.firebase.crashlytics.FlutterError: Null check operator used on a null value. Error thrown Instance of 'ErrorDescription'.
       at EmailModalBottomSheet.build.<fn>(build.java:58)

I guess supportedEmails[app.name]! raise the error because app.name is not present in your supportedEmails assets map.

I don't know what mailApps list you are providing to your widget, but I suggest you filter supported mailApps first instead of using '!' operator.
final supportedApps = mailApps.where((app) => supportedEmails.containsKey(app.name)).toList();

And I don't think you need HookWidget here :) StatelessWidget is enough

from open-mail-app-flutter.