My thinking goes:
- The fact it has survived a nuke and pave of Mojave is weird but that would seem to imply it is likely something that was restored after the nuke and pave.
- Since it occurs in a test account, it has to be something at the system level which leaves drivers, LaunchAgents, LaunchDaemons, and some kernel extensions.
- Since it occurs with a safe boot that would appear to eliminate all but essential kernel extensions.
- Since kernel extensions interact with hardware and firmware, resetting the NVRAM might change the behavior.
If my logic is sound that would point the finger at a third party kernel extension (If it were an Apple kernel extension a lot more people would be effected by the problem). The only troubleshooting technique I know of in such a case would be starting with a clean install of the bare OS and then adding third party kernel extensions one at a time until the problem re-appears (and I would not be surprised if it never re-appeared — that happened to me once).
However, with the imminent release of Catalina (rumors has it the Golden Master is in beta) and the fact there are a whole lot of
under the hood changes, I would wait to see if the problem exists in MacOS 10.15 before doing any more lengthy troubleshooting.
