[mediaqueries-5][editorial] Replaced deprecated term 'joint session history' by 'session history entry'

Author: SebastianZ

mediaqueries-5/Overview.bs

@@ -38,9 +38,7 @@ spec:css-values-4;
 		text:<resolution>
 	type:dfn; text:relative length
 spec:dom; type:dfn; text:origin
-spec:html;
-	type:dfn; for:/; text:browsing context
-	type:dfn; for:/; text:joint session history
+spec:html; type:dfn; for:/; text:browsing context
 spec:infra; type:dfn; text:user agent
 spec:selectors-4; type:selector;
 	text::fullscreen
@@ -2485,13 +2483,13 @@ Detecting UA-supplied navigation controls: the '@media/nav-controls' feature</h3
 		<dd>
 			The user agent does not have any [=obviously discoverable=] navigation controls,
 			and in particular none that cause the user agent
-			to move back one page in the [=joint session history=].
+			to move back to the page's previous <a href="https://html.spec.whatwg.org/multipage/browsing-the-web.html#session-history-entry">session history entry</a>.
 
 		<dt><dfn>back</dfn>
 		<dd>
 			The user agent provides navigation controls,
 			including at least an [=obviously discoverable=] control
-			causing the user agent to move back one page in the [=joint session history=]
+			causing the user agent to move back to the page's previous <a href="https://html.spec.whatwg.org/multipage/browsing-the-web.html#session-history-entry">session history entry</a>
 			(typically, a “back” button).
 	</dl>
 
@@ -2531,7 +2529,7 @@ Detecting UA-supplied navigation controls: the '@media/nav-controls' feature</h3
 	Whether [=obviously discoverable=] controls are active does not impact the evaluation of this media feature.
 
 	<div class=example>
-		If there is no previous page in the [=joint session history=],
+		If there is no previous <a href="https://html.spec.whatwg.org/multipage/browsing-the-web.html#session-history-entry">session history entry</a> for the page,
 		a user agent with a “back” button could toggle it to a disabled state
 		that cannot be interacted with until there actually is history
 		that can be navigated back to.