Not sure you understandd the problem:
I install spotify-dev without problem, but after logging in, it suddenly says I am in offline mode, it cannot reach the internet.
Turns out that after trying everything I found online to solve the issue it is as simple as disabling my VPN, suddenly Spotify can reach it’s servers and play music.
However, uninstalling spotify-dev and reinstalling spotify fixes the issue.
In other words, I probably should never update spotify again or it will stop working with my VPN. Unfortunately.