Forum Moderators: phranque
E.g. clicking on the full-size image link in IE generates a 403 as desired.
Clicking on the link in Firefox pulls up the image. The only way to get FF to act the same way as IE is to clear the cache before hitting the full-size image link.
Any idea how to get FF to act as expected when it comes to hotlink protection?
That's what this is, probably -- a caching issue.
If an image is successfully cached in your browser, then it will be served from that cache, and no request will be sent to your server. Therefore, server-side access-control code can have no effect.
You should always flush your cache(s) before every test of access-control code.
If you change the cache-control headers sent by your server, so that 'no-cache, must-revalidate' is sent, then any compliant browser will always check with the server before serving cached content. However, this partially offsets the advantages of caching, since it increases the number of requests to your server.
Jim