[css-values-5] Update issue about state of mix()

Author: fantasai

css-values-5/Overview.bs

@@ -934,7 +934,7 @@ Container Query Progress Values: the ''container-progress()'' notation</h3>
 <h2 id="mixing">
 Mixing and Interpolation Notations: the *-mix() family</h2>
 
-	ISSUE(6245): This section is an exploratory draft, and not yet approved by the CSSWG.
+	ISSUE(6245): This feature <a href="https://css.typetura.com/ruleset-interpolation/explainer/">does not handle multiple breakpoints very well</a>, and might need to be redesigned.
 
 	Several <dfn>mix notations</dfn> in CSS
 	allow representing the interpolation of two values,
@@ -3255,7 +3255,7 @@ Acknowledgments</h2>
 	L. David Baron,
 	Mike Bremford,
 	Sebastian Zartner,
-	and especially Scott Kellum
+	and <a href="https://github.com/w3c/csswg-drafts/issues/6245">especially Scott Kellum</a>
 	for their ideas, comments, and suggestions for Level 5;
 
 <h2 class="no-num" id="changes">