Proton VPN is open-source project with (GPL-3.0 license) that allow anyone to fork and publish their own version, and if you read "About this extension" you will see that it says:
"Swift Proton is a *fork* of the official Proton VPN browser extension"
Also, this version of Proton VPN browser extension has new UI + new features keeping the core-fucntion of the extension intact.
You can check my fork project here: https://github.com/AL-AM101/swift-proton-vpn-browser-extension
