Wikimedia Bugzilla is closed!

Whoops. The code that handles the redirect only appears to care about 'returnto' and 'returntoquery' params:

if ( $wgMFForceSecureLogin && WebRequest::detectProtocol() != 'https' ) {
			// get the https url and redirect
			$request = $special->getContext()->getRequest();
			$query = array(
				'returnto' => $request->getVal( 'returnto', '' ),
				'returntoquery' => $request->getVal( 'returntoquery', '' ),
			);
			$url = $mobileContext->getMobileUrl(
				$special->getFullTitle()->getFullURL( $query ),
				true
			);
			$special->getContext()->getOutput()->redirect( $url );
		}

This should be a quick fix.

https://gerrit.wikimedia.org/r/#/c/47606/1