Reproduction steps:
1. Open the Unity Hub
2. Change computer's user
3. Open the Unity Hub

Expected result: Unity Hub runs as usual
Actual result: Unity Hub is black

Reproducible with: 2.4.5, 3.0.0, 3.0.1, 3.1.2

Note: reproducible on macOS and Windows 10

More issues being reported here with 3.3-beta.1 when using multiple computer users: [https://unity.slack.com/archives/C7MKBJ34G/p1662560532839199]

From a second user account on Windows:
# Installing an editor fails from the second user account, failed message doesn't elaborate why. (Logs in thread for this.)
# The license shown and used on the second account is my Unity Pro license from my main user account - the account signed in to the Hub is new and should have no purchased licenses. I can remove the splash screen as this user.
# Switching user on Windows and opening the Hub on the second user account results in an endless loading screen for that Hub.