Browser Detection.. is bad.
Published April 16th, 2005
UMO uses browser detection to try to determine which version of some extensions you want to download. For example, the Enigmail Extension, you need a version for every OS, including Windows, Linux and OS X. Look at the Enigmail Page.
Well, I see a download for Windows, but I am using OS X. When you visit it, you might see it for Linux, or OS X — its hard to tell, since the page is cached with a Squid frontend, you get the download link for whatever OS viewed the page before you.
The solution is to add a
Vary: User-Agent HTTTP header, to make the cache use a different version of the Cache for every User Agent — and therefore show the correct download link. The bad news is that Squid doesn’t support the Vary header. I geuss the only option is Apache 2.1.
Written by Paul Querna, CTO @ ScaleFT. @pquerna