Image slide show transitions problem

Operating System Info

macOS 10.15

Other OS

No response

OBS Studio Version

27.2.4

OBS Studio Version (Other)

No response

OBS Studio Log URL

https://obsproject.com/logs/sbYwuAVSo9QaKSYT

OBS Studio Crash Log URL

No response

Expected Behavior

In Image Slide Show properties, when you select Transition > Fade, the slide show should fade properly in background (controlled by an hotkey) even if the source is hidden or a different scene is active. For example on a Fullscreen/Windowed projector (source).

Current Behavior

In Image Slide Show properties, when you select Transition > Fade and the (slide show) source is hidden or a different scene is active, on a Fullscreen/Windowed projector (source), using an hotkey to select next, the transition fade always from the last shown image when the scene or source was active (number "1"), not the actual image in the playlist. So the transition is not 1>2, 2>3, 3>4, 4>5 but 1>2, 1>3, 1>4, 1>5.

https://user-images.githubusercontent.com/103456067/162834620-d212643c-f98e-4ff4-9146-c3610b1de233.mp4

Steps to Reproduce

Anything else we should know?

It occurs also with Slide and Wipe transitions, not with Cut. With and without selecting "Loop" option.
It occurs only when the source is hidden or the source's scene is not active.
Same behaviour on Mac and Win (tested Win 10).

Start at the Image Slide Show source's transition handling and reproduce the issue with a hidden source or inactive scene, using the Fade, Slide, and Wipe options and a hotkey. Done means transitions advance from the current playlist image rather than repeatedly fading from the last image shown when the source was active.