Where do I find information about the reasons behind decisions made by the W3C?

Question

I use the :contains() selector extensively in Selenium tests. The W3C specification has removed it.

I want to understand why but could not find documentation that explains the reasoning behind this decision. Have looked at W3org (the pseudo class was last present in this version) and searched google.

Where do I find information on reasons for such changes made to W3C specifications?

Answer 1

You can probably find the reasoning on the W3C mailing lists:

https://www.google.com/search?q=site%3Ahttp%3A%2F%2Flists.w3.org%2F+css+contains

There's lots of discussions about it. According to this post, among others, it might have something to do with performance issues.