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Mozilla's Notifications API allows web pages to control the display of system notifications to the end user. These notifications are outside the top-level browsing viewport, so can be displayed even when the user has switched tabs or moved to a different app. The API is designed to be compatible with existing notification systems, across different platforms. It is available only in secure contexts (HTTPS) in some or all supporting browsers. As of Firefox 44, the permissions for Notifications and Push have been merged.