Some words for sysadmins: this is a rather annoying bug because there is not any sign in the logs that the client has a content decoding failure. You can never be sure that the user gets to see what the server sends to the client.
Jan Ehrhardt in gmane.comp.apache.devel (Sun, 06 Dec 2015 01:34:47 +0100): >I will try to intercept the compressed content and see if I can make a >static page out of it, outside of Drupal and without having to log in as >Drupal admin. If content decoding is successful, Chrome stores the compressed content in the cache. I saved such a file as admin_menu_encoded.txt.gz and made it available as https://tfrtst.sessionportal.net/admin_menu_encoded.php PHP-script: <?php // open the file in a binary mode $name = './admin_menu_encoded.txt.gz'; $fp = fopen($name, 'rb'); // send the right headers header("Content-Type: text/html; charset=utf-8"); // admin_menu_encoded.txt.gz is already gzip'ed, so make sure // zlib.output_compression does not compress it once more. ini_set('zlib.output_compression', '0'); header('Content-Encoding: gzip'); header("Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0"); header("Content-Length: " . filesize($name)); // dump the file and stop the script fpassthru($fp); exit; ?> The bummer: this file does not fail, whichever mod_http2 I load. Firefox also fails with mod_http2 1.0.7+ and gives some extra information in the headers: X-Requested-With: XMLHttpRequest The explanation: the drupal admin menu is loaded by JQuery, using an Ajax-call. The return value of that call is (1) decoded (gunzipped) and (2) loaded in a <div id="admin-menu"> almost at the end of the page. Yet that Ajax call is not the culprit either. If I enter the URL of the admin-menu directly Chrome reports a ERR_CONTENT_DECODING_FAILED and Firefox: >Content Encoding Error > >The page you are trying to view cannot be shown because >it uses an invalid or unsupported form of compression. > >Please contact the website owners to inform them of this problem. You will not see this message when the admin menu is loaded by JQuery. So far the analysis at this moment. I do not know what I could investigate now. Suggestions welcome. -- Jan
