During vCenter Server upgrade, the Storage size dropdown in the Select deployment size section displays as blank instead of showing Default.
vCenter Server 8.x
This is caused by the UI installer cache.
This is a UI issue.
You can continue with the upgrade even if you encounter this issue.
1. Stop UI installer application
2. Delete the vcsa-ui-installer directory containing the UI installer cache.
The vcsa-ui-installer directory is located at the following path:
C:\Users\<user>\AppData\Roaming\vcsa-ui-installer\
/home/<user>/.config/vcsa-ui-installer/
/Users/<user>/Library/Application Support/vcsa-ui-installer/