[.htaccess] Header set Access-Control-Allow-Origin in .htaccess doesn't work

I +1'd Miro's answer for the link to the header-checker site http://www.webconfs.com/http-header-check.php. It pops up an obnoxious ad every time you use it, but it is, nevertheless, very useful for verifying the presence of the Access-Control-Allow-Origin header.

I'm reading a .json file from the javascript on my web page. I found that adding the following to my .htaccess file fixed the problem when viewing my web page in IE 11 (version 11.447.14393.0):

<FilesMatch "\.(json)$">
  <IfModule mod_headers.c>
    Header set Access-Control-Allow-Origin "*"
  </IfModule>
</FilesMatch>

I also added the following to /etc/httpd.conf (Apache's configuration file):

AllowOverride All

The header-checker site verified that the Access-Control-Allow-Origin header is now being sent (thanks, Miro!).

However, Firefox 50.0.2, Opera 41.0.2353.69, and Edge 38.14393.0.0 all fetch the file anyhow, even without the Access-Control-Allow-Origin header. (Note: they might be checking IP addresses, since the two domains I was using are both hosted on the same server, at the same IPv4 address.)

However, Chrome 54.0.2840.99 m (64-bit) ignores the Access-Control-Allow-Origin header and fails anyhow, erroneously reporting:

No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin '{mydomain}' is therefore not allowed access.

I think this has got to be some sort of "first." IE is working correctly; Chrome, Firefox, Opera and Edge are all buggy; and Chrome is the worst. Isn't that the exact opposite of the usual case?

Examples related to .htaccess

Use .htaccess to redirect HTTP to HTTPs Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04 Server unable to read htaccess file, denying access to be safe Laravel 5 – Remove Public from URL Laravel 5 not finding css files How can I fix the 'Missing Cross-Origin Resource Sharing (CORS) Response Header' webfont issue? How Can I Remove “public/index.php” in the URL Generated Laravel? Apache 2.4 - Request exceeded the limit of 10 internal redirects due to probable configuration error Forbidden You don't have permission to access / on this server Htaccess: add/remove trailing slash from URL

Examples related to mod-rewrite

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04 Forbidden You don't have permission to access / on this server Htaccess: add/remove trailing slash from URL Permission denied: /var/www/abc/.htaccess pcfg_openfile: unable to check htaccess file, ensure it is readable? 404 Not Found The requested URL was not found on this server Redirect all to index.php using htaccess .htaccess not working on localhost with XAMPP URL rewriting with PHP No input file specified htaccess redirect to https://www

Examples related to rewrite

Rewrite URL after redirecting 404 error htaccess How to redirect single url in nginx? Header set Access-Control-Allow-Origin in .htaccess doesn't work convert htaccess to nginx rewrite a folder name using .htaccess

Examples related to cors

Axios having CORS issue Cross-Origin Read Blocking (CORB) Jquery AJAX: No 'Access-Control-Allow-Origin' header is present on the requested resource How to allow CORS in react.js? Set cookies for cross origin requests XMLHttpRequest blocked by CORS Policy How to enable CORS in ASP.net Core WebAPI No 'Access-Control-Allow-Origin' header is present on the requested resource—when trying to get data from a REST API How to overcome the CORS issue in ReactJS Trying to use fetch and pass in mode: no-cors