Disk Utility message "Updating boot support partitions for the volume as required" Finder crashed on a external drive which caused an abrupt eject. I rand Disk Utility over the drive and the operation finished with the message:


  Updating boot support partitions for the volume as required


Its a FAT32 partition, it already existed, and it was not bootable so its not clear to me what required updating.

What does the message "Updating boot support partitions for the volume as required" mean? Or how can I determine the changes were made?
The message from Disk Utility is simply there to tell you it's checking the hidden EFI partition (if present) and updating as necessary. In your case it won't be necessary so nothing will be updated.

Disk Utility performs this extra step if you run a disk repair on a parent disk rather than on one of the partitions within that disk.