Manual:$wgExtraNamespaces

Namespaces: $wgExtraNamespaces
Additional namespaces.
Introduced in version:	1.3.3
Removed in version:	still in use
Allowed values:	(array)
Default value:	[]
Other settings: Alphabetical | By function

Details

$wgExtraNamespaces configures additional, custom namespaces for a wiki. It can also be used to rename the default namespaces.

This is covered in detail in Manual:Using custom namespaces .

In case an extension should work with the newly created custom namespace, make sure that you define and name them prior to invoking the respective extension.

Extensions should not use this setting, instead they should use the CanonicalNamespaces hook or load the namespace through extension.json (MW 1.26+, Gerrit change 234146).

See also

• Namespace IDs used by extensions – Shows you a list of namespace IDs you should definitely avoid to prevent namespace conflicts, thus the first custom namespace may encounter conflicts even at ID 110 though 100 is theoretically possible. It is recommened to define custom namespaces with IDs starting at 3000 to avoid namespace conflicts.
• $wgExtraGenderNamespaces
• $wgNamespaceAliases