I'm using the IDE version 1.8.12 with MAC Catalina 10.15.3. If I attach a MEGA 2560 to my USB port, the port for the board is listed under TOOLS/PORT. If I connect the MKR VIDOR 4000, the port doesn't show even though I've selected the proper board. I know that this connection once worked in a previous version of the IDE and MAC. It's been a while since I tried so I don't know the versions. Does anybody have any ideas on how to get the port to show with the MKR 4000?
I found the solution to this problem. I discovered that all four of the micro USB cables that I tried where, in fact, just charging cables with no data connections. There was no way to tell from looking at the cables that they were charge only cables. I purchased a new cable that was specifically advertised as a data cable and it worked.