Just double checking: I have a <script> that calls a php file to compose the javascript. Just double checking: when a browser loads content from a <link> or <script> tag, it always sends the appropriate HTTP_USER_AGENT string as well, correct? I just want to sure it ALWAYS sends it before i rely on its functionality. Thanks
Yes, you can rely on HTTP_USER_AGENT always being sent. But you can't always rely on it being accurate. A malicious script can set the HTTP_USER_AGENT field to any value it chooses, so don't use it as a security control. Good luck!