The images are hidden deep, so you will need to change settings before you can view them. To do this, open File Explorer and go to the
View tab. On the far right is an Options button, click it.
In the window that opens, select the
View tab. Under Advanced Settings, select Show hidden files, folders and drives, then click Apply and then OK to close the open window.
Now it is time to navigate to the following directory (which was hidden before).
This PC > C: > Users > [Your User Name] > AppData > Local > Packages > Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy > LocalState > Assets
In this directory you will see a bunch of files without extensions. These are the incognito image files. These are
jpeg images of various resolutions to meet the needs of multiple devices screen sizes. You can copy the files to another location and rename them to have the jpeg extension, then you can open them with your default image viewer.
Source: https://superuser.com/questions/1126403/what-is-the-location-of-lock-screen-images-on-windows-10
