The RSSLog plugin refreshes it's content by a configurable amount of time. If another page than the one with the RSSLog widget is active during the refresh, the widget is empty afterwards when switching back to it's page.
Reason is, that the amount of visible lines is calculated by using the height of the widget. But when the containing page is not active, the height is 0. Therefore no single line is shown.
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Reason is, that the amount of visible lines is calculated by using the height of the widget. But when the containing page is not active, the height is 0. Therefore no single line is shown.