[css-color-4] Update changes

Author: svgeesus

css-color-4/Overview.bs

@@ -6273,7 +6273,14 @@ Changes</h2>
 </h3>
 
 <ul>
-	<li>Editorial refactoring.</li>
+	<!-- to 1 Sept 2022 -->
+	<li>Clarified how missing values in colors to be interpolated are carried forward</li>
+	<li>Updated syntax of xyz-params so they take numbers and percentage, to align with prose</li>
+	<li>Ensure all examples and figures have IDs, self-links</li>
+	<li>Clarified importance to implementors of reading the gamut mapping introduction</li>
+	<li>Removed left-over mention of custom color spaces (feature was moved to CSS Color 5)</li>
+	<li>Refactor syntax of &lt;color> and &lt;alpha-value></li>
+	<li>Editorial refactoring for better reading order.</li>
 	<li>Updated pseudocode for gamut mapping algorithm, remove un-needed deltaE calls</li>
 </ul>