First I want to give kudos to the Stellarium developers. This is a great program!
I use Stellarium often and set up many Locations for the various sites that I observe at.
The default locations that come with Stellarium are nice but I prefer to hide them and just see only the locations that I have created.
I'm sure the following procedure is not supported.. so use at your own risk.. but it worked well for me with 12.4 and earlier versions.
The default locations are stored in an archive file named base_locations.bin.gz.
Note that we kept (renamed) the original base_locations.bin.gz file so you can always delete or rename your modified version and rename the original back to base_locations.bin.gz to see the default locations again.
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