Troubleshooting for multiple interference issues


I’m using Tailscale in a complex scenario, in which it is used alongside Eddie (AirVPN’s Windows App,, Oracle’s VM, VirtualBox, Glasswire and lately Portmaster (Safing Portmaster) with a lot of issues.
In this scenario, I closed Portmaster, because it gives me a lot of headache. While others are somehow active (I mean VirtualBox is only active with its Network adapter), when I first connect with Tailscale, then create a VPN connection with Eddie, I can use it until I disconnect Eddie, there seems to be issues with that internet could not be recognized as connected anymore. In this case, I preferred to disable VirtualBox’s network adapter, but the solution is to disconnect Eddie and Tailscale, enable VirtualBox’s network adapter and disable it again. The connection can be recognized as valid then.
What could be the real culprit for this complex problem? Can you help me?

I will forward this issue to all possible interference participants as well.