RewriteRule works for everyone except IE?

Question

htaccess

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^ http://(www\.)?mydomain\.ru [NC]
RewriteCond %{HTTP_REFERER} !^ http://(www\.)?mydomain\.ru.*$ [NC]
RewriteRule ^1.jpg$ 2.jpg [L,QSA]
This works great, users of my site see one picture, users of another site that shows part of mine through an iframe see a completely different one. But not in IE/Edge. For some reason, the redirect does not work for these browsers.