The problem with "fixing" the user-agent string is that making it easier to pass/use only means web-developers will find it easier to continue to abuse it. In

The problem with "fixing" the user-agent string is that making it easier to pass/use only means web-developers will find it easier to continue to abuse it. In an ideal world web-developers should be testing if individual pieces of functionality exist rather than inferring what is supported based on the browser. I think JS does a fairly good job of allowing developers to test for functionality, unfortunately CSS does not. I am well aware that it is meant to "fail gracefully" but to a lot of developers they want to supply alternative looks where functionality isn't available and CSS doesn't lend itself to that. So you wind up inferring CSS support from JS support which is just as broken as inferring JS support from the browser's version/name/platform.