A browser tab left in the background stops doing work. This is deliberate on the browser's part — it saves battery and memory on the tabs you are not looking at — but one of the things it suspends is the live connection that keeps generation views, your credit balance and your notifications current. Within minutes that connection is gone, and it does not return by itself when you come back to the tab.
Until now the page simply stayed as it was. We recently began saying so, with a note that live updates are off next to the refresh control. That note told you what had happened, but the remedy was still yours to apply: refresh, or reload.
Returning to the tab is now enough. When you bring one of these pages back into view, the application checks whether its live connection is still delivering and, if it is not, restores it — renewing your session first, so the reconnection is not immediately rejected. The note disappears a moment later, and updates resume arriving as they did before. Your credit balance and any notifications that arrived while you were away are fetched at the same time, so nothing is left behind.
Nothing happens when nothing is wrong: an ordinary switch between tabs with a working connection costs nothing at all. And if the connection cannot be restored, the note stays where it is rather than the page pretending otherwise — refreshing still works, exactly as before.