getgrav
Scheme detection problem
It is not a Grav issue per se, since it originates in psr7-server/ServerRequestCreator.php. I reported the issue upstream, but I have no way of knowing if it will be resolved there and in the meantime it will keep affecting Grav anyway.
To the point: recently I have installed Grav on a server which reports both $_SERVER['HTTPS'] as on and at the same time $_SERVER['REQUEST_SCHEME'] as http. I should add that on this setup I am using Grav with HTTPS exclusively. The problem manifests itself when a trailing slash redirection is on, so, for example, on admin login page or on any page with a trailing slash, for that matter, like https://example.com/about/. The latter will be redirected to http://example.com:443/about which causes the 400 error. The direct cause of this is the way the $request object is initialized and psr7's URI scheme is detected. It's in this fragment of https://github.com/Nyholm/psr7-server/blob/master/src/ServerRequestCreator.php:
https://github.com/Nyholm/psr7-server/blob/b846a689844cef114e8079d8c80f0afd96745ae3/src/ServerRequestCreator.php#L272-L276
It sets URI's scheme as http regardless of the fact that HTTPS header is on and port is 443. I tried to modify the URI using withScheme() method in handleRedirectRequest() in InitializeProcessor, but it didn't change the scheme.
