See T348388#9916271. We need to complete T368125: Clean up existing unattached accounts first.
Things to change:
- When user is locally renamed, it will be automatically connected to a new global user. If the target global user does not exist, one will be created with credential duplicated from original one
- (need test) New system users should be connected to CentralAuth
- ...
Things to drop:
- T288906: Remove or rewrite CentralAuth SUL migration code
- globalnames table
- localnames table
- users_to_rename table
- centralauth-merge right
- centralauth-unmerge right (rename to centralauth-delete instead)
- Special:MergeAccount
- $wgCentralAuthAutoMigrate
- $wgCentralAuthAutoMigrateNonGlobalAccounts
- $wgCentralAuthStrict
- $wgCentralAuthDryRun
- CentralAuthUnattachUserJob
- CentralAuthUser::listUnattached
- ...
TODO
TODO