Lower than 100% Zoom BROKEN

OK, if I understood, you mean that part of the window when reduced will NOT reduce the image as well…?
I would like to point out that you’re not showing the same filter in the 2 screenshots, also the filter > https://i.ibb.co/Q8q530G/BROKEN.png that you call “Broken” is a deprecated filter (I had to find it, because you’re showing only filters in your Fav, which are renamed)

Anyway, maybe it has something to do with this > [Solved] Half preview left or right bug? in 3.4.1 but not sure at all.

But I think I have a good news, slide to the right first until you see the full image, then slide to the left and it will reduce its size, it worked for me (I did try only with the deprecated filter) :wink:
This will not reduce an image bigger than the window view, though (like very zoomed in image)

Hope this help