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Modals should be movable, allowing the user to reposition them.
Error
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messages
Error text should be succinct and unambiguous. The nature of the error should be described first, followed by additional information such as the rule which has not been met or the reason for the error, then lastly the recommended action for the user:
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Display of content based on user permissions
If a user’s permissions do not allow them access to a feature or content then it should not be displayed.