"Sandboxie is a sandbox-based isolation software for 32- and 64-bit Windows NT-based operating systems."
https://sandboxie-plus.com/
The application provides built-in portability feature which works flawlessly. Though it still would be nice to have it in the PortableApps repository.
https://portableapps.com/comment/243977#comment-243977
“My brain is only a receiver, in the Universe there is a core from which we obtain knowledge, strength and inspiration. I have not penetrated into the secrets of this core, but I know that it exists.”
― Nikola Tesla ―
It refers to Sandboxie, not Sandboxie-Plus. Moreover, I've been using Sandboxie-Plus in portable mode for a while and I haven't encountered any issue. It has built-in clean-up&removal at shutdown feature.