how is url.intended set?

My website In vendor/laravel/framework/src/Illuminate/Routing/Redirector.php there's this method:

    /**
     * Create a new redirect response to the previously intended location.
     *
     * @param  string  $default
     * @param  int     $status
     * @param  array   $headers
     * @param  bool    $secure
     * @return \Illuminate\Http\RedirectResponse
     */
    public function intended($default = '/', $status = 302, $headers = [], $secure = null)
    {
        $path = $this->session->pull('url.intended', $default);

        return $this->to($path, $status, $headers, $secure);
    }

If $default is 'backend/backend' then $path winds up being http://mywebsite.com/backend/backend instead of https://mywebsite.com/backend/backend. ie. I want it to return https intsead of http.

I'm doing \URL::forceScheme('https'); in the service provider but it doesn't matter.

I see that the guest() method in Redirector.php sets url.intended but that method isn't being called.

I'm running Laravel 5.5.

Any ideas?

via Chebli Mohamed