"the top-level browsing context" is used several times in the spec. However that term is not defined in HTML. Instead HTML defines the top-level browsing context of another browsing context. You need to start with a browsing context to get the top-level one!
don't make any sense. Whose top-level browsing context? Presumably the intent is not any top-level browsing context, i.e. it's not a valid target to observe a completely different tab...
197 is part of this, but the problem is deeper.
"the top-level browsing context" is used several times in the spec. However that term is not defined in HTML. Instead HTML defines the top-level browsing context of another browsing context. You need to start with a browsing context to get the top-level one!
So statements like
don't make any sense. Whose top-level browsing context? Presumably the intent is not any top-level browsing context, i.e. it's not a valid target to observe a completely different tab...