The Quick Announcement Bar app has a feature called Delay Before Repeating, that lets you configure a bar to only display if it has not been seen for a certain amount of time.
How it works:
Let’s say your “Delay Before Repeating” is set to 20 seconds
When a customer visits the website, the bar will display right away. When the customer visits another page, the bar will do the math and calculate whether it should display again. If the Interval Time has not been exceeded, then it will not display.
This feature can be used along with "Disappear After" to ensure that the bar does not appear frequently. Please click here for additional details.