Repositories

The new Dropbox API v2 require that you are running your site using https ($CFG->sslproxy = true;)

global $CFG;
$callbackurl = self::callback_url()->out(false);
if ($CFG->loginhttps) {
    $callbackurl = str_replace("http://", "https://", $callbackurl);
}
$url = new moodle_url($this->auth_url(),
         array('client_id' => $this->clientid,
           'response_type' => 'code',
            'redirect_uri' => $callbackurl,
                   'state' => $this->returnurl->out_as_local_url(false),
                   'scope' => $this->scope,
));
return $url;

I am also able to use the Dropbox API V2.

As far as I see, the other repositories are working fine (when I also updated my Google account oauth2 return url to use https).

Anyone an idea what else can go wrong after this change?