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Appears:
after a component or section finishes loading, and there is no data to show.
when a specific user action has yet to be taken, for example, no items added/selected.
Disappears:
when some content is populated, either due to a user action or external change.
Either because of a user action (populates the state with content) or a process that changes the state (e.g. server is responsive again).
Best Practices
Do:
Use short, clear, and informative messages underneath the visual.
Guide the user to perform a relevant action.
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