[alreq] Isolation not fully supported (#215)

r12a has just created a new issue for https://github.com/w3c/alreq:

== Isolation not fully supported ==
Safari still doesn't apply bidi isolation to an element that has a `dir` attribute (although a shim based on CSS works fine).

This creates significant issues for managing bidirectional text.

(The old Edge still doesn't support directional isolation, but Edge has now moved to Blink, which does support it.)

Please view or discuss this issue at https://github.com/w3c/alreq/issues/215 using your GitHub account