Opera VPN is built directly into the browser apps and doesn’t require registration. Yet, a strict no-log policy is crucial for a VPN.
https://www.techradar.com/pro/vpn/operavpn-never-logs-your-activities-independent-auditors-confirm
https://www.techradar.com/pro/vpn/operavpn-never-logs-your-activities-independent-auditors-confirm