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Updating the Alert Message
You can can change the message without requiring users to re-acknowledge it or you can save it as a new message to cause the message to be prominently displayed again.
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If you need to make a minor change to the text that you want users to see if they haven’t already seen the message then simply make your change to the text and press the Save button. Any use user who has already seen your original text will not be required to view the new text.
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