'Internationalizing Flutter apps' page issue

[mnarsely]

Page URL: https://flutter.dev/docs/development/accessibility-and-localization/internationalization.html
Page source: https://github.com/flutter/website/tree/master/src/docs/development/accessibility-and-localization/internationalization.md

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Description of issue: Adding an unsupported locale to Flutter is not working properly to NumberFormat and DateFormat symbols and patterns.

I am getting the following error whenever I refresh my app after changing to a newly supported language

`The following ArgumentError was thrown building:
Invalid argument(s): Invalid locale "en_US"

When the exception was thrown, this was the stack
#0 _throwLocaleError
package:intl/src/intl_helpers.dart:177
#1 verifiedLocale
package:intl/src/intl_helpers.dart:171
#2 verifiedLocale
package:intl/src/intl_helpers.dart:156
#3 new DateFormat
package:intl/…/intl/date_format.dart:266
#4 new DateFormat.yMEd
package:intl/…/intl/date_format.dart:478`

[micpap25]

Hi @mnarsely,
Can you be more specific on what the website is missing or how the website is incorrect?
If this is a personal issue, you might find more help on a site like StackOverflow. Then, if you feel like something on the website was lacking, you can let us know here.

[mnarsely]

My bad, I am taking this issue somewhere else, thank you @micpap25