With #31412 applied, open https://au.gmented.com/p/video/test.html. With --legacy-layout there are media controls that appear. When using layout 2020, they do not appear. These controls rely on a special shadow host setup in the legacy layout implementation (

). I'm not really clear where the right place to slot this into the new layout engine is.