How long a photo stays up is a setting now. It was fixed at a minute.
On the device: Settings → Display → Time per photo, from fifteen seconds to an hour. In Home Assistant: Slideshow time per photo, which takes any number of seconds between five and 3600, so you are not limited to the seven choices on the screen. Set something in between there and the screen shows the nearest choice below it.
Home Assistant also gains a read-only Slideshow folder, naming the folder the photos come from. Picking it still happens on the device, under Photo folder, where you can browse your media sources a level at a time.
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