Let |topLevelBC| to the [=browsing context=] with [=top-level browsing context/system focus=] if one exists, or return false.
Let |focusedDocument| be the |topLevelBC|'s currently focused area's [=Node/node document=].
If |relevantGlobal|'s [=relevant settings object=]'s [=origin=] is [=same origin-domain=] with |focusedDocument|'s [=origin=], return true.
In Compute Pressure we do the following: