Hi,
I have recently noticed a bug in nautilus 3.36.3 in Fedora 32 workstation. When I press the spacebar key to preview a video, it opens in a small preview window as expected. However, when I try to close it, It opens a larger preview window of the same video. Closing this newly opened larger preview window keeps opening itself again and again until we close nautilus. The preview feature works perfectly fine with images. I have only tried out with “.mkv” video files.