I'll post here the same thing I posted on another HN post about user agent strings [0], because it's still relevant. I'll also add that the MS article link artf

I'll post here the same thing I posted on another HN post about user agent strings [0], because it's still relevant. I'll also add that the MS article link artfully dodges the whole "we suck at UA sniffing" issue their own products have. Asp.Net 2.0 (and up to 3.5, which is still framework 2.0) sites use UA sniffing to determine which markup to emit for many built-in controls, like Asp:Menu. When Yosemite / iOS 8 / Safari 8 was released, anyone with a SharePoint 2007/2010 site had their navigation get all screwy. I know first hand how infuriating someone's badly designed UA sniffing can be; it happened to me, and I wrote up a fix for it [1]. Why did it happen in the first place? Where did the UA sniffing fall apart? A poorly designed RegExp looking for "60" in Safari's UA without a word boundary or EOL check. The new Safari UA includes "600" in the relevant section, and suddenly SharePoint sites were sending markup intended for (now) ancient browsers - browsers that weren't even on the compatibility list for SharePoint in the first place. UA sniffing does need to go away for determining what structure your markup sends to the user agent. Edit: linked to earlier comment mentioned at beginning of this one [0]: https://news.ycombinator.com/item?id=8647749 https://news.ycombinator.com/item?id=8647749 [1]: http://blog.sharepointexperience.com/2014/10/did-safari-or-ios-8-break-your-sharepoint-2010-site/ http://blog.sharepointexperience.com/2014/10/did-safari-or-i...