Visiting certain pages downloads gzip file instead of displaying them

Question

I've encountered an intermittent problem with my site. When visiting pages, the browser just downloads a .gz file instead of loading the page. Reloading the page a few times will eventually display the page correctly. The majority of the time, it occurs when visiting pages on the wiki (part of the site), but I've had it happen once on the main part of the site, too.

I'm using MediaWiki's file cache, but not the built-in gzip compression (it displays gibberish). I'm using mod_deflate (enabled according the host's instructions) and mod_pagespeed for the entire site. The tricky thing with this issue is that I can't accurately reproduce it. It pops up now and then, for apparently no reason.

My .htaccess:

AddType image/svg+xml svg svgz
AddEncoding gzip svgz

AddType application/x-font-woff woff

AddDefaultCharset utf-8

# mod_deflate
AddOutputFilterByType DEFLATE text/text text/html text/plain text/xml text/css application/x-javascript application/javascript

<FilesMatch "\.(html|htm)$">
  Header unset Etag
  Header set Cache-control "max-age=0, no-cache"
</FilesMatch>

<FilesMatch "\.(jpg|jpeg|gif|png|js|css|woff|ttf|svg)$">
  Header unset Etag
  Header set Cache-control "public, max-age=604800"
</FilesMatch>

<IfModule pagespeed_module>
  ModPagespeed on
  ModPagespeedEnableFilters extend_cache
  ModPagespeedEnableFilters collapse_whitespace
  ModPagespeedEnableFilters combine_css
  ModPagespeedEnableFilters move_css_to_head
  ModPagespeedEnableFilters remove_comments
</IfModule>

# Wiki ShortURLs
RewriteEngine On
RewriteRule ^/?wiki(/.*)?$ %{DOCUMENT_ROOT}/w/index.php [PT,L,QSA]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^/?w/images/thumb/[0-9a-f]/[0-9a-f][0-9a-f]/([^/]+)/([0-9]+)px-.*$ %{DOCUMENT_ROOT}/w/thumb.php?f=$1&width=$2 [L,QSA,B]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^/?w/images/thumb/archive/[0-9a-f]/[0-9a-f][0-9a-f]/([^/]+)/([0-9]+)px-.*$ %{DOCUMENT_ROOT}/w/thumb.php?f=$1&width=$2&archived=1 [L,QSA,B]

The wiki cache settings are the following:

$wgMainCacheType    = CACHE_ANYTHING;
$wgMemCachedServers = array();

$wgUseFileCache         = true;
$wgFileCacheDirectory   = "$IP/cache";
$wgShowIPinHeader       = false;
$wgUseGzip              = false;

The server is using PHP version 5.3.14 and all of the files on the non-wiki part of the site are .php files. Pages show a Content-Encoding of gzip. The site is hosted on GoDaddy and this issue has, so far, only appeared in Chrome (ver 22.0.1229.79 m), although I haven't extensively tested Firefox and IE for this problem yet.

There is almost no load on the site at the moment (just a handful of people testing). The only wiki extensions I have installed are: ConfirmEdit, Gadgets, ListRedLinks, Nuke, ParserFunctions, Renameuser, Vector, and WikiEditor. Everything else is stock.

So, my question is: what is causing this problem, why does it only show up at random, and how can I fix it?

Answer 1

The problem lies with the browser not the installation.

It appears that the Google Chrome browser has some sort of caching problem. I found that when I cleared the browser cache, the problem went away.