If I install PortableApps.com on my flash drive, do any files get left behind on the C:/ drive, or are all the files contained on the flash drive? I'm concerned because even though I'm downloading it to the flash drive, the downloading window suggests that it might still be placing some files on the C:/ drive.
https://portableapps.com/support
Use Portable Apps on both Flash Drive and HDD/SSD.