After 60 flights I finally had a scare.  Clear line of sight, disconnect for seemingly no reason.  RTH worked thankfully but I would iike to understand what may have happened.
When I use the Assistant 2 software i can see the firmware but when I go to flight data nothing shows up other than an open data viewer button.   Tutorials show that a list of dated files should be there for download.  What am I missing?

Did you install the latest version of DJI assistant?
Have you tried to reinstall it? Please post a screenshot here if convenient.

What I found was when I opened the Data Viewer, the Mavic also did some sort of switch to the storage mode, so when I viewed the Mavic's data drive in the Finder (OSX) I was able to browse the data files. The instructions were not at all clear about this, but I somehow (maybe half accidentally) figured this out.