Finder Cover flow alloactes second FIFinderSync

I have a finder extension and have noticed that when I switched the finder display mode to 'cover flow' that a second instance of the FIFinderSync is allocated and then after that calling:
[[FIFinderSyncController defaultController] setBadgeIdentifier:overlayID forURL:url];


fails to set the badges anymore. I noticed that Dropbox has the same problem.


Should I be using something other than [FIFinderSyncController defaultController] or is this a bug in the finder?


I am running 10.13.5.

Finder Cover flow alloactes second FIFinderSync
 
 
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