Enables fallback update mode where tt-rss tries to update feeds in background while tt-rss is open in your browser. If you don't have a lot of feeds and don't want to or can't run background processes while not running tt-rss, this method is generally viable to keep your feeds up to date. Still, there are more robust (and recommended) updating methods available, you can read about them here: https://tt-rss.org/wiki/UpdatingFeeds.
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