I use my .htaccess file to restrict image hotlinking from my website and have some conditions to allow Facebook, Google, Reddit, and Twitter... it's been working fine but suddenly today Twitter is only showing my protected image on new posts that I link to.

Here is the rule I have in place:

RewriteCond %{HTTP_REFERER} ! ^ http(s)?://(www.)?twitter.com [NC]

(spaces added around the ! ^ http because of reddit formatting messing it up)

Does Twitter use a CDN or other domain to reach out and grab images? Why is this not working correctly?

Thank you!

UPDATE: I figured it out, I had to actually escape the period in the domain for some reason... so this works:

RewriteCond %{HTTP_REFERER} ! ^ http(s)?://(www.)?twitter.com/ [NC]

(again spaces added to keep Reddit from formatting it)