Tailscale doesn't open in CasaOS

Hey everyone. I have my CasaOS running on Ubuntu Server and I've decided to set up the external access to it. For some reason port forwarding didn't work (maybe I've done it wrong) so I've decided to use Tailscale instead. I went to the CasaOS' app store and downloaded it. But when I click to open the app, it opens a new tab with CasaOS instead of Tailscale. What might be the problem?