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The list can be viewed at menu -> Manage -> Networks -> View List Networks.
Networks can be added to the list at menu -> Manage -> Networks -> Add NetworkCreate Networks.
Networks can have a description added by clicking the Edit Network link on the View Network page.
You can disable the feature in the config (menu -> Admin -> Community -> ConfigAll Configuration) by changing the value of blessed_subnets_use to 'n' (sans quotes).
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