Finder image thumbnails break

There are a number of problems with displaying image thumbnails in finder. All problems started with macOS 15 update. Now I'm on 15.2 and problems persist. (MBP M1Max, 32Gb, 1Tb) **Images with wrong extensions are not displayed.** I download a lot of images from reddit and other places, and sometimes there can be jpeg with a name "pic.png" - as long as it has that name finder won't render it's thumbnail. I rename it to "pic.jpg" and now thumbnail is correct. Similarly, webp can't be named jpg, and jpg can't be named webp. It kinda makes sense to require extensions to match the file type, but on all previous versions it wasn't a problem. And it's not like I rename files on purpose, they are provided by websites like that. QuickLook (spacebar) has no problem displaying such files, but Finder thumbnail (little file icon) only works with proper extension. **DNG files break thumbnails completely.** Let's say there is folder A with a lot of JPGs, folder B with just a couple of DNG, and folder C with a few more JPG's. I open folder A - everything looks fine. I open folder B - I see dng icons instead of thumbnails. I open folder C - default icons for jpg, no thumbnails. I still see thumbnails in folder A, as they are cached. But any new folders with any image types that are not cached won't render. Fans start to spin and system monitor shows high cpu (400%) and ram (6Gb) for **ImageThumbnailExtension** process. Killing it does nothing, it respawns with less ram and it will get there eventually. **qlmanage -r** **qlmanage -r cache** **killall com.apple.quicklook.ThumbnailsAgent** These commands suggested by chatGPT also won't fix a problem. But restarting the Mac will fix it, until I open folder with DNGs again. 😐 I thought - perhaps it's some 3rd party app that can't handle DNG files. I've uninstalled capture one and photoshop, DNG icons now look like Preview icons, name of file type changed to localized, so I assume they are rendered with system apps and not 3rd party ones. But problem persists. Some 3rd party thumbnail / quicklook plugins also broke, such as affinity. While it's not macOS problem by itself, clearly apple has changed enough to mess up 3rd party plugins, so developers have to do extra work to fix that. Do you have any suggestions? I doubt I'm the only one to have such a problem.