A live data source that quietly returned nothing used to look perfectly healthy while the slide it fed stayed blank. Several changes close that gap.
A fetch that returns nothing usable is now a failure
Point a feed at a web page instead of the feed itself, or give it credentials it cannot use, and the source is marked as failing, shows the reason on the Content Sources page and alerts your admins. A source that has never worked says so explicitly.
A live slide cannot be saved without a source
Dynamic slides that need live data now require you to choose the source before you can save them, so a slide can no longer reach a screen showing unfilled placeholders.
Hide a slide when its source has nothing to show
Any live slide can now be set to disappear from the rotation while its source is empty, rather than showing an empty panel. Previously this was only possible for one specific kind of source.
What this means for you: a broken feed reaches you instead of your audience.