[css-transforms-2] One more place that should refer to perspective(none).

Fixing the neutral element for addition was missed when making changes
for perspective clamping and for adding 'perspective(none)'.

Followup to #6488 and #413.

Author: dbaron

css-transforms-2/Overview.bs

@@ -1337,7 +1337,7 @@ Addition and accumulation of transform lists {#combining-transform-lists}
 Neutral element for addition {#neutral-element}
 ----------------------------
 
-Some animations require a neutral element for addition. For transform functions this is a scalar or a list of scalars of 0. Examples of neutral elements for transform functions are ''translate(0)'', ''translate3d(0, 0, 0)'', ''translateX(0)'', ''translateY(0)'', ''translateZ(0)'', ''scale(0)'', ''scaleX(0)'', ''scaleY(0)'', ''scaleZ(0)'', ''rotate(0)'', ''rotate3d(v<sub>x</sub>, v<sub>y</sub>, v<sub>z</sub>, 0)'' (where <var ignore>v</var> is a context dependent vector), ''rotateX(0)'', ''rotateY(0)'', ''rotateZ(0)'', ''skew(0, 0)'', ''skewX(0)'', ''skewY(0)'', ''matrix(0, 0, 0, 0, 0, 0)'', ''matrix3d(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)'' and ''perspective(0)''.
+Some animations require a neutral element for addition. For transform functions this is a scalar or a list of scalars of 0. Examples of neutral elements for transform functions are ''translate(0)'', ''translate3d(0, 0, 0)'', ''translateX(0)'', ''translateY(0)'', ''translateZ(0)'', ''scale(0)'', ''scaleX(0)'', ''scaleY(0)'', ''scaleZ(0)'', ''rotate(0)'', ''rotate3d(v<sub>x</sub>, v<sub>y</sub>, v<sub>z</sub>, 0)'' (where <var ignore>v</var> is a context dependent vector), ''rotateX(0)'', ''rotateY(0)'', ''rotateZ(0)'', ''skew(0, 0)'', ''skewX(0)'', ''skewY(0)'', ''matrix(0, 0, 0, 0, 0, 0)'', ''matrix3d(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)'' and ''perspective(none)''.
 
 Note: Animations to or from the neutral element of additions <<matrix()>>, ''matrix3d()'' and ''perspective()'' fall back to discrete animations (See [[#matrix-interpolation]]).
 
@@ -1454,6 +1454,7 @@ Recent Changes</h3>
 		<li>Add support for a ''perspective()/none'' argument to ''perspective()'' (see <a href="https://github.com/w3c/csswg-drafts/issues/6488">#6488</a>).</li>
 		<li>Define that clamping of values of ''perspective()'' also applies to resolved values and interpolation (see <a href="https://github.com/w3c/csswg-drafts/issues/6320">#6320</a> and <a href="https://github.com/w3c/csswg-drafts/issues/6346">#6346</a>).</li>
 		<li>Clarify that the effects of ''transform-style/preserve-3d'' only affect <a>transformable elements</a> (see <a href="https://github.com/w3c/csswg-drafts/issues/6430">#6430</a>).</li>
+		<li>Fixed the <a href="#neutral-element">neutral element for addition</a> for ''perspective()'' to be ''perspective(none)''
 		<li>Added a note that the resolved value of 'translate' includes percentages (see <a href="https://github.com/w3c/csswg-drafts/issues/2124">#2124</a>).</li>
 		<li>Describe 3D sorting more precisely, to explain which descendants are included, and not limit Appendix E reference to steps 1-7 (see <a href="https://github.com/w3c/csswg-drafts/issues/926">#926</a>).</li>
 	</ul>