Does it matter if it's published? BTW, checking for the referer header content will cause some browsers to fail, depending on the mode. See https://en.wikipedi

Does it matter if it's published? BTW, checking for the referer header content will cause some browsers to fail, depending on the mode. See https://en.wikipedia.org/wiki/HTTP_referer#Referer_hiding https://en.wikipedia.org/wiki/HTTP_referer#Referer_hiding , which lists some of the reasons for why a browser might send a blank value. The check that the User Agent contains "Mozilla 5.0" will cause text-mode users (eg, links) to fail. While not popular, I use links to download some tar.gz files from sourceforge and a few other places because it's easier to start the download that way than get the actual download URL through a graphical browser.