[css-color-5] Removed special casing of 100% from the color-mix() algorithm, thus avoiding a discontinuity near fully-transparent colors #14014

Author: svgeesus

css-color-5/Overview.bs

@@ -295,12 +295,14 @@ Otherwise, use the specified colorspace for mixing.
 	1. [=Normalize mix percentages=] from the list of [=mix items=] passed to the function,
 		with the "forced normalization" flag set to true,
 		letting |items| and |leftover| be the result.
+	<!-- 
 	2. If |leftover| is 100%,
 		return [=transparent black=],
-		converted to the specified interpolation <<color-space>>.
-	3. Let |alpha mult| be <code>1 - |leftover|</code>,
+		converted to the specified interpolation <<color-space>>. 
+	-->
+	2. Let |alpha mult| be <code>1 - |leftover|</code>,
 		interpreting |leftover| as a number between 0 and 1.
-	4. If |items| is length 1,
+	3. If |items| is length 1,
 		set |color| to the color of that sole item,
 		converted to the specified interpolation <<color-space>>.
 
@@ -328,8 +330,8 @@ Otherwise, use the specified colorspace for mixing.
 				and a percentage of |combined percentage|,
 				and [=stack/push=] it onto |item stack|.
 		3. Set |color| to the color of the sole remaining item in |item stack|.
-	5. Multiply the alpha component of |color| by |alpha mult|.
-	6. Return |color|.
+	4. Multiply the alpha component of |color| by |alpha mult|.
+	5. Return |color|.
 
 	Note: In [=cylindrical polar color=] spaces,
 	mixing is order-dependent,