The @inert attribute is getting some traction from the Google Chrome team.
Core effort was done as part of bug 110952.
(In reply to comment #2)
> Core effort was done as part of bug 110952.
That patch barely touches the surface of what's needed to support `inert` in WebKit.
*** This bug has been marked as a duplicate of bug 165279 ***
Mass move bugs into the DOM component.