Preview scaling bug with effects
From website:
There’s an issue with the preview scaling with rotoscoping and other filters. If I apply the filter using a preview scale of let’s say 270p, when I change the preview back to 1:1 or render the video the filter is in a different part of the screen. If I change back to 270 it looks alright.
Related to: https://bugs.kde.org/show_bug.cgi?id=433018