[css-overflow-3] Overflow anchor is dependent on alignment, actually, so say that. Also fix linking error.

Author: fantasai

css-overflow-3/Overview.bs

@@ -282,7 +282,7 @@ Scrollable Overflow: the 'overflow-x', 'overflow-y', and 'overflow' properties</
 	is clipped to its padding edge,
 	and if so,
 	whether it is a <dfn>scrollable box</dfn>
-	that allows the user to scroll clipped parts of its <a>scrollable area</a>
+	that allows the user to scroll clipped parts of its <a>scrollable overflow region</a>
 	into view.
 
 	<pre class=propdef>
@@ -448,8 +448,10 @@ Scrolling Origin, Direction, and Restriction</h3>
 	with respect to its border box,
 	prior to any user or programmatic scrolling that changes it,
 	is dependent on the box’s <a>writing mode</a>,
-	and is the <a>block-start</a>/</a>inline-start</a> edge
+	and is by default the <a>block-start</a>/</a>inline-start</a> edge
 	of the box’s <a>padding edge</a>.
+	However, the 'align-content' and 'justify-content' properties [[!CSS-ALIGN-3]]
+	can be used to change this.
 
 	Due to Web-compatibility constraints
 	(caused by authors exploiting legacy bugs to surreptitiously hide content from visual readers but not search engines and/or speech output),