This is a sub-task of #1775842: [meta] Convert all variables to state and/or config systems
This is not state - it's configuration. However this requires more thought as the point of this variable is to avoid a database query and putting this in config will result in a database query.
Do we have a place to store this that won't result in a db query at this point? Even if it goes to config it will either get pulled from cache or read from a file (which is probably worse than the query.)
I do agree that this is config though, right now its main utility is to set IPs in $conf which is only acknowledged in the config system.
Please see #1479466: Convert IP address blocking to config system.
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