Steps to reproduce:

1. Go to https://www.w3.org/TR/wai-aria-practices/examples/treegrid/treegrid-1.html
2. Use linear navigation to get to TreeGrid (not tab navigation)

Actual behavior:

Table not detected

Expected behavior:

User should be able to interact with tree-grid using SR per navigation pattern: https://www.w3.org/TR/wai-aria-practices/examples/treegrid/treegrid-1.html.

Note that same page works with JAWS