Manual:$wgUseCodexSpecialBlock

Miscellaneous settings: $wgUseCodexSpecialBlock
Whether to use Codex in Special:Block form.
Introduced in version:	1.42.0 (Gerrit change 1005609; git #22dc49a5)
Removed in version:	Still in use
Allowed values:	(boolean)
Default value:	false
Other settings: Alphabetical | By function

Warning:

This is a temporary feature flag.