Keep slide show tab alive—Safari locks it in incognito mode

[gy-mate]

Is your feature request related to a problem?
Yes, when I open the slide show in full screen in Safari Private Browsing, the browser locks the window after ~10 minutes. This means that it also exits from the full screen view. (live example)

Describe the solution you'd like
Somehow keep the tab alive (like YouTube does) to avoid Safari locking it.

Describe alternatives you've considered
Disabling the Require Touch ID to view locked tabs option in Safari. While this is a good workaround, it's not as convenient.