With HTML5 Please, you can just search for a feature that you are looking to use and find out how to do so. If you think our recommendation is incorrect, you can edit the recommendation for each feature and send a pull request.
Divya provides a little backstory for HTML5 Please which is a great resource to see feature support for not only HTML5 but CSS3, etc. I bookmarked the project when it first got started on github and have found it extremely useful and glad to see it actually launch. Don't forget CSS3 Please if you haven't seen it yet either. I love how amazing and large the standards community has gotten in recent years and projects like these and H5BP are great for everyone.