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Do not use page alerts just for styling regular content (for emphasis or highlighting)
Do not use page alerts to provide information about a normal step in a process or task
Do not use page alerts to tell the user about a problem that’s affecting the service as a whole – Use product alerts instead
Best Practices
Do
Display page alerts after a change in context, for example, when a user clicks a link or submits a form, launching a new page or an updated view
Write concise headings and copy - Provide further details in the appropriate section or page
Place page alerts underneath the page or subsection heading, as applicable
Ensure that page alerts include headings that clearly convey the purpose of the alert (for example, “Warning”)
Use an appropriate status – Please see the Guidelines for Alerts article
Don’t
Display alerts that are not related to the user’s current goal
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