Solved, though I'm not sure exactly what fixed it...

  1. I disabled my sole other plugn-in --> markdown-prettier + restarted joplin - no change.
  2. uninstalled markdown-prettier + restarted joplin - no change.
  3. uninstalled joplin-batch, reinstalled old version + restarted joplin - no change.
  4. uninstalled joplin-batch, installed new version, restarted - FIXED.
  5. uninstalled new joplin-batch version, reinstalled old version, restarted - still FIXED
  6. reinstalled markdown-prettier, restarted - still FIXED.

Regardless, thanks for the help. The (old) plugin is now scanning for unused resources.