PSU System Variables aren't accessible in 2.5.0

[PorreKaj]

Could this be relevant?

Variable issue after upgrade

I just found a workaround: I had the Environment for the dashboard set to “Default”. However, if it change it to anything else (7.1.4, Windows PowerShell 5.1, or Integrated), it works just fine. If I go to Settings → General, I see that no Default Environment is selected. I would be interested to know why the “Default” environment works in the old version but not the new.