[css-fonts-5] Clarified that if "from-font" references a metric which the first available font does not have, it is the same as "none". w3c#6384

Author: svgeesus

css-fonts-5/Overview.bs

@@ -223,10 +223,9 @@ Issue(8792):
 		<dt><dfn>from-font</dfn>
 		<dd>
 			Computes to the <<number>> corresponding to
-			the specified metric of the [=first available font=].
-
-			ISSUE(6384): Shouldn't this be the first available font
-			that can provide the required metric?
+			the specified metric of the [=first available font=],
+			if it exists. 
+			Otherwise, the same as ''none''.
 	</dl>
 
 	<wpt>
@@ -706,7 +705,7 @@ Issue(5484):
 
 
 <h2 id="font-feature-variation-resolution">
-Font Feature and Variation Resolution</h3>
+Font Feature and Variation Resolution</h2>
 
 Issue(5635):