Nothing worked. I dropped the MicroSDXC card and cannot find it now. Thanks all for your replies.
Well, I was going to suggest dropping it in the trash, but that'll work ;-)
They have a lifespan, and I've toasted more than one in a dashcam. It's good it didn't reformat, since it would probably have corruption that you might not have noticed when it was in the cam.
And as to the future of programs, Micromat now has version of TechTool Pro 13 out, which does work with APFS and can even manage the APFS shapshots for recovering files. And bunches of other stuff.
Whether it's worth it, I don't know. I've found it useful on occasion after I switched from DiskWarrior (not sure they're even developing now). Many of the thing TT does, like some repair, formatting, cloning, etc, can be done with Disk Utility or via the Terminal. But that's true of lot of other utilities like other cloners and synchers. I have been using it so long it pays off just for the ease of making say custom bootable thumb drives and such, but others might not find that so. But I imagine a change in processors won't change it much going forward.
Yes but...
From Micromat:
"It is understandable to conclude that Mojave, or Catalina support and APFS support would mean the same thing. However, the operating system and the file system are, in fact, distinct from one another. While the operating system serves as the 'window' for interacting with drives in many ways, there is no API for dealing with the disk directly.
The current documentation from Apple does not include sufficient information to write a tool to defragment APFS volumes. The extent of the documentation on the subject so far is a feature flag labeled NX_FEATURE_DEFRAG which indicates whether an APFS container supports defragmentation.
If Apple releases additional documentation that provides sufficient information for manipulating the data directly on disk, we will explore whether a defragmentation feature is feasible for *rotational* APFS drives. Defragmentation on Solid State Drives in the traditional sense will not be supported, as organizing data on solid state devices only serves to increase wear, and provides no performance benefit.
Likewise, while the Volume Rebuild can repair many drives with volume structures problems, a full rebuild that reorganizes the volume structures can only be implemented once Apple provides further documentation.
It is important to note as well that Techtool Pro uses a low-level API to test, repair, rebuild, and defragment Mac OS Extended volumes. No such API yet exists for APFS, and it is unclear if Apple will make one available."
