Bug: Using multiple "Size, Position & Rotate" filters in vertical mode goes weird

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OS and Version (please complete the following information):

• Operating System: Ubuntu 24.04.3 LTS
• Shotcut Version: 25.08.16 Installed from the main ubuntu OS store Ubuntu snap on snapcraft io

Describe the bug
Using two "Size, Position & Rotate" filters one after another goes crazy.
The workflow is from this video, using Motion Tracker that gets applied in one filter and zoom in a secound filter: https://www.youtube.com/watch?v=cUGB7vUE45M&t=630s
I have a vertical video, if I put two "Size, Position & Rotate" filters on the track without changing the default at all, the video gets stretched horizontally. Same if I try to put one on the track and a second on the clip. Some things can get even crazier where I touch the zoom with the scrollbar up and down for 0.1% and the vertical size gets to 0 even due I'm again at 100% zoom.
Seem to only happen for Vertical projects, seems ok on wide projects at least on first look.

Steps To Reproduce
Start a new project, as custom ratio, select vertical (3840x2160 24.00fps 2ch)
Open a video (I'm using a 4k 3840 × 2160 H.265 48231 kbps 25.00 frames per second)
Create track (getting the video on the track). (I'm using proxy and preview scaling if that matters)
Of the track, hit filters,
add your first "Size, Position & Rotate" filter
add a second "Size, Position & Rotate" filter
Look at the resulting preview (You can play or scroll it's all stretched looking)
If you change the size mode on the first filter from Fill to distort it looks fine.

Expected behavior
Putting two "Size, Position & Rotate" filters without changing any setting shouldn't do anything to the video

Screenshots

Reproduce the issue in Shotcut with a vertical project by adding two default "Size, Position & Rotate" filters to the track, then compare the result with a wide project and with the first filter set to Distort. Trace the filter processing involved in that workflow. Done means multiple default filters no longer stretch or otherwise distort vertical video.