Dialogs and shadow DOM: can we make it accessible?

Last year, I wrote about managing focus in the shadow DOM, and in particular about modal dialogs. Since the <dialog> element has now shipped in all browsers, and the inert attribute is starting to land too, I figured it would be a good time to take another look at getting dialogs to play nicely with shadow DOM.

This post is going to get pretty technical, especially when it comes to the nitty-gritty details of accessibility and web standards. If you’re into that, then buckle up! The ride may be a bit bumpy.