Vid.stab deshake strange flickering video (ONLY ON PREVIEW)

i supposed that this was an issue with the deshake settings.. but the rendering is OK vidtab

(i just changed the zoom value... no other changes) this happens on my PC with OPEN-GL or DirectX back-ends (Windows version with latest build)

and.. looking a the forum there is a linux users with something similar (without deshake effect)

https://drive.google.com/file/d/1xv4o_UkDLA2gjGXmy3ADmmBNIrccAeSi/view?usp=sharing

and this is the forum post: https://forum.kde.org/viewtopic.php?f=265&t=168017&p=437867#p437867