Manual:$wgAssumeProxiesUseDefaultProtocolPorts

Server URLs and file paths: $wgAssumeProxiesUseDefaultProtocolPorts
When the wiki is running behind a proxy and this is set to true, assumes that the proxy exposes the wiki on the standard ports.
Introduced in version:1.26.0 (Gerrit change 219901; git #b2768298)
Removed in version:still in use
Allowed values:(boolean)
Default value:true

Details edit

When the wiki is running behind a proxy and this is set to true, assumes that the proxy exposes the wiki on the standard ports (443 for HTTPS and 80 for HTTP).