Automatic saved png

Before quitting Blender asks if I want to save my textures. Which I love, but where does it save it automatically?

I answered yes and instead of asking me where to save it just quit. When I turned the project back on, the texture was still there. Even though it is not bond to anything.

In the picture I saved by hand the green marked one. I am interested to find out where is the red marked one is (Riba Normal.001). I tried looking for it with the search function on my drives, 0 results. Is it saved inside the project?