Manual:$wgProxyKey

From mediawiki.org
HTTP proxy (CDN) settings: $wgProxyKey
Deprecated, replaced by $wgSecretKey
Introduced in version:1.3.0
Deprecated in version:1.4.0
Removed in version:1.24.0 (Gerrit change 138991; git #5e48ad2e)
Allowed values:(string), false
Default value:false
'W1svekXc5u6lZllTZOwnzEk1nbs' (before deprecation)