Ethernet via Thunderbolt intermittently disconnects when using Luna

use Luna to connect my MacBook Pro mid-2015 to my iMac late-2015 desktop. Both are connected directly to my AirPort Extreme base station via Ethernet. The MacBook also has the wireless connection enabled. Both machines are running macOS Catalina 10.15.4. The MacBook Pro is connected to Ethernet via an Apple Thunderbolt to Ethernet adapter. The Ethernet connect is prioritized above the Wi-Fi connection in the Network preferences.

I am using Luna 4.0.3 (3139)

I am finding that the Ethernet connection on the MacBook “drops” after a period of use. It is active and connected, and then when it “drops” the status shows as the Ethernet cable is unplugged. It will reconnect if I unplug, and plug the thunderbolt adapter back into the MacBook (but not if I plug or unplug the Ethernet cable itself).

This appears to be associated with the Luna use, as Ethernet drops as described above do not seem to happen unless Luna is connected to the secondary display on the iMac. I have not every experienced any issues when connecting over WiFi.

Is this a problem you have had anyone talk about before? Anything I can try?

Many of us had problems with Luna 4.0.3 running on the latest version of macOS 10.15.4. Try this beta version and see if it works better:

Thanks for the advice. It eventually turned out that it was a problem with the Thunderbolt-Ethernet adapter (quite odd actually), and I purchased a new adapter and it has been fine for quite some time.