You will get D+ alerts for actions not blocked by the sandbox, so you will get more D+ alerts if you select the restriction setting Unrestricted
, and fewer if you select Untrusted
“Always trust the publisher of this file” is only for digitally signed files. Only if a file is signed can its publisher be verified.
There is no Remember my answer in the elevated privileges alert. Instead, if you allow, the file is added to My Own Safe Files.foobar2000 installer is not signed, and Spotify installer is digitally signed by Spotify Ltd.