All the standard namespaces have a default access key ('C' 'T' in most cases) defined by the message MediaWiki:Accesskey-ca-nstab-<canonical ns name>. But custom namespaces only have accesskey 'T' for their talkspaces. I think 'C' should be default accesskey also for custom namespaces. ('C' could also be used for Project namespace, which currently has accesskey 'A' unlike all other default namespaces.)
Version: 1.17.x
Severity: normal