Events are not displayed even when the "Read Event Filter" is off, if all events are read

• Step 1: Make sure that the "Read Events Filter" is off
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• Step 2: A notification alert is displayed
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• Step 3: I click the check box to mark it as read
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• Step 4: I refresh the page and the notification event is gone!
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It was expected that the event wouldn't be hidden since the "Read Event Filters" is about "Hide notifications that you have marked as read" and it's off.