When I scanned my system drive with "WizTree" (a program for viewing disk usage stats), I have found out that there is a "mager.onnxe" 288 MB file in the Windows 10 "Photos" app ("C:\Program Files\WindowsApps\Microsoft.Windows.Photos_...").
What is it? Can I delete it?
It's really obscure, but I just found an answer - https://www.bleepingcomputer.com/forums/t/799174/mystery-file-mageronnxe-300597649-bytes/?p=5703763
"mager.onnxe" is an ONNX model for a component of a Microsoft project called Perceptive Shell.
It is accompanied with a library, magerapi.dll.
Looking around it quickly shows that "mager" is an abbreviation for... "Magic Eraser".
Which is an internal name for a Microsoft Photos feature, called Generative Erase.Here's some docs: https://support.microsoft.com/en-us/windows/using-generative-erase-in-microsoft-photos-e0b4df42-3372-4dfd-9d28-c4ef408454a7
So, if you really need to delete it (if you need additional 288 MB of disk space), and you don't use the "Magic Eraser" feature (and won't use it in the future), then you can delete it (or move it somewhere else).
I just checked, and it accesses the file only when you select the "Magic Eraser" option, so the app should work just fine.
Though, you can't delete it that simple, because the file owner is "SYSTEM", so you don't have a permission to do anything with this file, unless messing with the permissions/owner or something else.