Added content-visibility:hidden

source

@@ -76170,12 +76170,13 @@ body { display:none }
   data-x="fip-active-match">active match</span> using the <span>find-in-page interface</span>.</p>
 
   <p>When find-in-page begins searching for matches, all <code>details</code> elements in the page
-  which do not have their <code data-x="attr-details-open">open</code> attribute set should have
-  their second slot act as if it is added to the rendering without modifying the <code
-  data-x="attr-details-open">open</code> attribute in order to make find-in-page able to search
-  through it. After find-in-page finishes searching for matches, those <code>details</code> elements
-  should have their second slot be removed from the rendering again. This entire process must happen
-  synchronously (and so is not observable to users or to author code).</p>
+  which do not have their <code data-x="attr-details-open">open</code> attribute set should have the
+  <a href="https://drafts.csswg.org/css-contain-2/#skips-its-contents">skipped contents</a> of their
+  second slot become accessible. without modifying the <code data-x="attr-details-open">open</code>
+  attribute in order to make find-in-page able to search through it. After find-in-page finishes
+  searching for matches, those <code>details</code> elements should have their contents become
+  skipped again. This entire process must happen synchronously (and so is not observable to users or
+  to author code).</p>
 
   <p>When find-in-page chooses a new <span data-x="fip-active-match">active match</span>, perform
   the following steps:</p>
@@ -115871,9 +115872,9 @@ details[open] > summary {
   <p>The <code>details</code> element's first <code>summary</code> element child, if any, is
   expected to allow the user to request the details be shown or hidden.</p>
 
-  <p>The <code>details</code> element's second <span data-x="concept-slot">slot</span> is expected
-  to be removed from the rendering when the <code>details</code> element does not have an <code
-  data-x="attr-details-open">open</code> attribute.</p>
+  <p>The <code>details</code> element's second <span data-x="concept-slot">slot</span> must have the
+  style <code>"display:block; content-visibility:hidden"</code> when the <code>details</code>
+  element does not have an <code data-x="attr-details-open">open</code> attribute.</p>
 
   <!-- https://mail.gnome.org/archives/usability/2006-June/msg00015.html -->