I made the (idiotic) decision to install a beta version of OS X
Mojave Big Sur, which later became corrupted, forcing me to reinstall OS X Catalina.
During the time that I had
Mojave Big Sur installed, I opened Photos which migrate the library to its new format. My
Pictures folder was archived by Backblaze.
After I installed Catalina, I attempted to open the Photos library (restored from Backblaze) and got this message:
I don't recall the process exactly, but I was able to open Photos which included some of the original photos. As you can see, this new library (highlighted) is substantially smaller than the other libraries:
How do I get the photographs and the meta data from my older library?