Using someone else’s credentials is a violation of Deezer's Terms of Service. While Deezer is historically slower to ban than Spotify, they do crack down on obvious credential stuffing. If the account associated with the ARL is banned, the free rider loses access immediately.
ARL (Address Relative Limit) is a cookie token used by Deezer to authenticate user sessions without requiring a standard password
: On the left sidebar, expand the Cookies section and click on https://www.deezer.com .
The ARL is a long string of alphanumeric characters stored in your browser's cookies after you log in. It acts as a "key" that third-party tools use to access Deezer's library.