This was mentioned by another GPSMAP 67 series user on the gpsrchive forums (not sure if he is active here). But after updating to device software version 8.90, the Setup > About screen shows both version 8.80 and 8.90. The first line on the screen reads Software Version 8.90, and the line Host Software Version reads 8.80 (can't post screenshots anymore otherwise I would have added one).
Garmin Express detects software version 8.80 and does not offer an update to 8.90. The GarminDevice.xml file on the unit also lists software version 8.80.
Guess something went wrong with releasing the 8.90 update? Does that mean the issue fixed in 8.90 is not actually fixed?