This is why you should test for capabilities, not agent strings. I propose a new string called "capabilities" which is a delimited list of standardized test suite sections your browser passes.<p>Of course, your browser could lie about its capabilities, as many Direct3D drivers do. And you will still need to test in every single browser, as game developers need to hire labs to test on the 150 most popular 3D cards.<p>Although, a web browser IS web-connected :-)
We could have another new string which is "I swear I am actually this browser and version." and someone (<i>cough</i> Google? <i>cough</i>) could create a web service with a mapping of real browser agent string to real tested no-foolies caps.