[selectors-4] Terminology edits to the :visited footnote #11151 (#11695)

* Add a few terminology fixes to the :visited links footnote

* Attempt to fix formatting and one origin reference

Author: kyraseevers

selectors-4/Overview.bs

@@ -4259,7 +4259,7 @@ while still preserving as much of the <em>usefulness</em> of '':visited'' as pos
 	containing [=tuples=] of three pieces of information:
 	* a visited [=/URL=]
 	* an [=/origin=] for the site that started a navigation
-	* an [=/origin=] for the top-level site containing the frame that started the navigation.
+	* a [=/site=] for the top-level site containing the frame that started the navigation.
 		(This will often be the same as the previous,
 		but can differ if the user clicks a link in a iframe, for example.)
 
@@ -4270,8 +4270,8 @@ while still preserving as much of the <em>usefulness</em> of '':visited'' as pos
 	add an entry to |visited history|
 	recording the navigation's destination URL,
 	the origin of the page containing the link or script,
-	and the origin of the top-level site containing that page
-	(which might be the same as the previous origin).
+	and the (schemeful) site of the top-level site containing that
+	page (which might be the same site as the previous origin).
 
 	Note: This allows a site to see '':visited'' information
 	for links that the user has clicked
@@ -4280,9 +4280,10 @@ while still preserving as much of the <em>usefulness</em> of '':visited'' as pos
 	where the site is A.
 
 	Additionally, add an entry to |visited history|
-	recording the destination's URL,
-	and the <em>destination's</em> origin
-	for both origin values.
+	recording the destination's URL, the <em>destination's</em>
+	origin, and the <em>destination's</em> site. Do this only
+	for navigations from top-level frames or iframes which are
+	same-origin with their top-level frame.
 
 	Note: This allows for a site to see '':visited'' information about its own pages
 	(which is already observable by the site)
@@ -4304,11 +4305,11 @@ while still preserving as much of the <em>usefulness</em> of '':visited'' as pos
 	only allow it to match '':visited'' if
 	the link's destination,
 	the origin of the page containing the link,
-	and the origin of the top-level site containing the link
+	and the top-level site containing the link
 	match a tuple in |visited history|.
 
 <div class=note>
-	The inclusion of both page origin and top-level site origin
+	The inclusion of both page origin and top-level site
 	prevents several possible privacy attacks,
 	such as: