Slideshow strange behavior after CPU filter

What is your operating system?
MacOS 13.5.2 Silicon M2 8Gbram

What is your Shotcut version (see Help > About Shotcut)?
23.09.02

Can you repeat the problem? If so, what are the steps?
(Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)
I’m creating a slideshow joined with a background video, at some point I placed in a track 20 imgs with 1sec of duration each, the issue begin once I apply a CPU filter for color correction to each img (applying a filter to the whole track gives the same behavior). After that most of the imgs are not shown in the timeline preview (neither in the exported video) and it shows only one or few imgs of the track. Removing the CPU filters or using GPU filters make all imgs back.
Is anything already known? It seems that by using a 4sec duration for each img it works regardless the filter applied.

For Slideshows an slow Zoom effect is applied by the Keyframe feature. To avoid this you have to precut and prepare your photos to the exact size outside of Shotcut and include it. If you choose 0% Zoom no Keyframes are used by default in this case. If you do not want to preedit the photos outside of Shotcut you have to deactivate all Keyframe Zoom Filters to not get weird effects for each photo of the diashow manually.

Thanks Alex007,

I’ve been able to reproduce it even on win10 version 23.07.29.
I found a workaround while trying to replicating it by using a short background video… it turned out that splitting the background video during the transition from one img to the next forces the renderer (melt ?) working as expected.

If You like see the screen recording of both:

BUG

Bug FIX

the exported video is the same as timeline preview.
Maybe this would be helpful on investigating on what happens behind.