diff --git a/content/about/coverage-and-quality/coverage-and-quality-report.html b/content/about/coverage-and-quality/coverage-and-quality-report.html
index cad4d60acb..95e47d0f3f 100644
--- a/content/about/coverage-and-quality/coverage-and-quality-report.html
+++ b/content/about/coverage-and-quality/coverage-and-quality-report.html
@@ -369,7 +369,6 @@ <h2 id="roles_with_more_than_one_label">Roles with More than One Guidance or Exa
                 <li><a href="../../../content/patterns/switch/examples/switch-button.html">Switch  Using HTML Button</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
             </ul>
 </td>
@@ -704,7 +703,6 @@ <h2 id="roles_with_more_than_one_label">Roles with More than One Guidance or Exa
             <td><ul>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
             </ul>
 </td>
@@ -715,7 +713,6 @@ <h2 id="roles_with_more_than_one_label">Roles with More than One Guidance or Exa
             <td><ul>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
             </ul>
 </td>
@@ -963,7 +960,6 @@ <h2 id="props_with_more_than_one_label">Properties and States with More than One
                 <li><a href="../../../content/patterns/treegrid/examples/treegrid-1.html">Treegrid Email Inbox</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
             </ul>
 </td>
@@ -1071,7 +1067,6 @@ <h2 id="props_with_more_than_one_label">Properties and States with More than One
                 <li><a href="../../../content/patterns/tabs/examples/tabs-manual.html">Tabs with Manual Activation</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
                 <li><a href="../../../content/patterns/landmarks/examples/complementary.html">Complementary Landmark</a></li>
                 <li><a href="../../../content/patterns/landmarks/examples/form.html">Form Landmark</a></li>
@@ -1183,7 +1178,6 @@ <h2 id="props_with_more_than_one_label">Properties and States with More than One
                 <li><a href="../../../content/patterns/tabs/examples/tabs-manual.html">Tabs with Manual Activation</a> (<abbr title="High Contrast Support">HC</abbr>)</li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1a.html">File Directory Treeview  Using Computed Properties</a></li>
                 <li><a href="../../../content/patterns/treeview/examples/treeview-1b.html">File Directory Treeview  Using Declared Properties</a></li>
-                <li><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li>
             </ul>
 </td>
           </tr>
@@ -1278,7 +1272,7 @@ <h3 id="example_summary">Coding Summary</h3>
         <tbody>
           <tr>
             <th scope="row">Total Examples</th>
-            <td id="example_summary_total">61</td>
+            <td id="example_summary_total">60</td>
           </tr>
           <tr>
             <th scope="row">High Contrast Documentation</th>
@@ -1294,7 +1288,7 @@ <h3 id="example_summary">Coding Summary</h3>
           </tr>
           <tr>
             <th scope="row">Uses <code>event.KeyCode</code></th>
-            <td id="example_summary_keycode">17</td>
+            <td id="example_summary_keycode">16</td>
           </tr>
           <tr>
             <th scope="row">Uses <code>event.which</code></th>
@@ -1306,11 +1300,11 @@ <h3 id="example_summary">Coding Summary</h3>
           </tr>
           <tr>
             <th scope="row">Use Prototype</th>
-            <td id="example_summary_prototype">23</td>
+            <td id="example_summary_prototype">22</td>
           </tr>
           <tr>
             <th scope="row">Mouse Events</th>
-            <td id="example_summary_mouse">16</td>
+            <td id="example_summary_mouse">15</td>
           </tr>
           <tr>
             <th scope="row">Pointer Events</th>
@@ -2104,19 +2098,6 @@ <h3 id="example_coding_practices">Coding Practices</h3>
             <td>6</td>
             <td>aria-label</td>
           </tr>
-          <tr>
-            <td><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></td>
-            <td>prototype</td>
-            <td>Yes</td>
-            <td></td>
-            <td></td>
-            <td>ex1</td>
-            <td>3</td>
-            <td>3</td>
-            <td>4</td>
-            <td>3</td>
-            <td>aria-label</td>
-          </tr>
           <tr>
             <td><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a></td>
             <td>class</td>
@@ -2627,16 +2608,6 @@ <h3 id="example_graphics_techniques">Graphics Techniques</h3>
             <td></td>
             <td>Yes</td>
           </tr>
-          <tr>
-            <td><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></td>
-            <td></td>
-            <td></td>
-            <td></td>
-            <td></td>
-            <td>Yes</td>
-            <td></td>
-            <td>Yes</td>
-          </tr>
           <tr>
             <td><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a></td>
             <td>Yes</td>
@@ -2784,11 +2755,6 @@ <h3 id="example_mouse_pointer">Mouse and Pointer Events</h3>
             <td>Yes</td>
             <td></td>
           </tr>
-          <tr>
-            <td><a href="../../../content/patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></td>
-            <td>Yes</td>
-            <td></td>
-          </tr>
           <tr>
             <td><a href="../../../content/patterns/treeview/examples/treeview-navigation.html">Navigation Treeview</a></td>
             <td>Yes</td>
diff --git a/content/about/coverage-and-quality/prop-coverage.csv b/content/about/coverage-and-quality/prop-coverage.csv
index d57b8cc3de..7effc0b049 100644
--- a/content/about/coverage-and-quality/prop-coverage.csv
+++ b/content/about/coverage-and-quality/prop-coverage.csv
@@ -14,7 +14,7 @@
 "aria-disabled","0","3","Example: Alert Dialog","Example: Editor Menubar","Example: Toolbar"
 "aria-dropeffect","0","0"
 "aria-errormessage","0","0"
-"aria-expanded","0","23","Example: Accordion","Example: Editable Combobox With Both List and Inline Autocomplete","Example: Editable Combobox With List Autocomplete","Example: Editable Combobox without Autocomplete","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Disclosure (Show/Hide) for Answers to Frequently Asked Questions","Example: Disclosure (Show/Hide) for Image Description","Example: Disclosure Navigation Menu with Top-Level Links","Example: Disclosure Navigation Menu","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Actions Menu Button  Using aria-activedescendant","Example: Actions Menu Button  Using element.focus()","Example: Navigation Menu Button","Example: Editor Menubar","Example: Navigation Menubar","Example: Toolbar","Example: Treegrid Email Inbox","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties","Example: Navigation Treeview"
+"aria-expanded","0","22","Example: Accordion","Example: Editable Combobox With Both List and Inline Autocomplete","Example: Editable Combobox With List Autocomplete","Example: Editable Combobox without Autocomplete","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Disclosure (Show/Hide) for Answers to Frequently Asked Questions","Example: Disclosure (Show/Hide) for Image Description","Example: Disclosure Navigation Menu with Top-Level Links","Example: Disclosure Navigation Menu","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Actions Menu Button  Using aria-activedescendant","Example: Actions Menu Button  Using element.focus()","Example: Navigation Menu Button","Example: Editor Menubar","Example: Navigation Menubar","Example: Toolbar","Example: Treegrid Email Inbox","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: Navigation Treeview"
 "aria-flowto","0","0"
 "aria-grabbed","0","0"
 "aria-haspopup","0","9","Example: Date Picker Combobox","Example: Editable Combobox with Grid Popup","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Actions Menu Button  Using aria-activedescendant","Example: Actions Menu Button  Using element.focus()","Example: Navigation Menu Button","Example: Editor Menubar","Example: Navigation Menubar","Example: Toolbar"
@@ -22,7 +22,7 @@
 "aria-invalid","0","0"
 "aria-keyshortcuts","0","0"
 "aria-label","1","18","Guidance: Naming with a String Attribute Via aria-label","Example: Breadcrumb","Example: Auto-Rotating Image Carousel  with Buttons for Slide Control","Example: Auto-Rotating Image Carousel with Tabs for Slide Control","Example: Editable Combobox With Both List and Inline Autocomplete","Example: Editable Combobox With List Autocomplete","Example: Editable Combobox without Autocomplete","Example: Date Picker Combobox","Example: Date Picker Dialog","Example: Link","Example: Editor Menubar","Example: Navigation Menubar","Example: Rating Radio Group","Example: Horizontal Multi-Thumb Slider","Example: Date Picker Spin Button","Example: Table","Example: Toolbar","Example: Treegrid Email Inbox","Example: Navigation Treeview"
-"aria-labelledby","1","41","Guidance: Naming with Referenced Content Via aria-labelledby","Example: Accordion","Example: Alert Dialog","Example: Checkbox  (Two State)","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Date Picker Dialog","Example: Modal Dialog","Example: Infinite Scrolling Feed","Example: Data Grid","Example: Layout Grid","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Listbox  with Grouped Options","Example: Listboxes with Rearrangeable Options","Example: Scrollable Listbox","Example: Actions Menu Button  Using aria-activedescendant","Example: Actions Menu Button  Using element.focus()","Example: Navigation Menu Button","Example: Navigation Menubar","Example: Meter","Example: Radio Group  Using aria-activedescendant","Example: Rating Radio Group","Example: Radio Group  Using Roving tabindex","Example: Color Viewer Slider","Example: Rating Slider","Example: Media Seek Slider","Example: Vertical Temperature Slider","Example: Date Picker Spin Button","Example: Switch  Using HTML Button","Example: Tabs with Automatic Activation","Example: Tabs with Manual Activation","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties","Example: Navigation Treeview","Example: Complementary Landmark","Example: Form Landmark","Example: Main Landmark","Example: Navigation Landmark","Example: Region Landmark","Example: Search Landmark"
+"aria-labelledby","1","40","Guidance: Naming with Referenced Content Via aria-labelledby","Example: Accordion","Example: Alert Dialog","Example: Checkbox  (Two State)","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Date Picker Dialog","Example: Modal Dialog","Example: Infinite Scrolling Feed","Example: Data Grid","Example: Layout Grid","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Listbox  with Grouped Options","Example: Listboxes with Rearrangeable Options","Example: Scrollable Listbox","Example: Actions Menu Button  Using aria-activedescendant","Example: Actions Menu Button  Using element.focus()","Example: Navigation Menu Button","Example: Navigation Menubar","Example: Meter","Example: Radio Group  Using aria-activedescendant","Example: Rating Radio Group","Example: Radio Group  Using Roving tabindex","Example: Color Viewer Slider","Example: Rating Slider","Example: Media Seek Slider","Example: Vertical Temperature Slider","Example: Date Picker Spin Button","Example: Switch  Using HTML Button","Example: Tabs with Automatic Activation","Example: Tabs with Manual Activation","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: Navigation Treeview","Example: Complementary Landmark","Example: Form Landmark","Example: Main Landmark","Example: Navigation Landmark","Example: Region Landmark","Example: Search Landmark"
 "aria-level","0","2","Example: Treegrid Email Inbox","Example: File Directory Treeview  Using Declared Properties"
 "aria-live","0","5","Example: Alert","Example: Auto-Rotating Image Carousel  with Buttons for Slide Control","Example: Auto-Rotating Image Carousel with Tabs for Slide Control","Example: Date Picker Combobox","Example: Date Picker Dialog"
 "aria-modal","0","4","Example: Alert Dialog","Example: Date Picker Combobox","Example: Date Picker Dialog","Example: Modal Dialog"
@@ -40,7 +40,7 @@
 "aria-rowcount","1","2","Guidance: Using aria-rowcount and aria-rowindex","Example: Data Grid","Example: Layout Grid"
 "aria-rowindex","1","2","Guidance: Using aria-rowcount and aria-rowindex","Example: Data Grid","Example: Layout Grid"
 "aria-rowspan","1","0","Guidance: Defining cell spans using aria-colspan and aria-rowspan"
-"aria-selected","0","17","Example: Auto-Rotating Image Carousel with Tabs for Slide Control","Example: Editable Combobox With Both List and Inline Autocomplete","Example: Editable Combobox With List Autocomplete","Example: Editable Combobox without Autocomplete","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Date Picker Dialog","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Listbox  with Grouped Options","Example: Listboxes with Rearrangeable Options","Example: Scrollable Listbox","Example: Tabs with Automatic Activation","Example: Tabs with Manual Activation","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties"
+"aria-selected","0","16","Example: Auto-Rotating Image Carousel with Tabs for Slide Control","Example: Editable Combobox With Both List and Inline Autocomplete","Example: Editable Combobox With List Autocomplete","Example: Editable Combobox without Autocomplete","Example: Date Picker Combobox","Example: Select-Only Combobox","Example: Editable Combobox with Grid Popup","Example: Date Picker Dialog","Example: (Deprecated) Collapsible Dropdown Listbox","Example: Listbox  with Grouped Options","Example: Listboxes with Rearrangeable Options","Example: Scrollable Listbox","Example: Tabs with Automatic Activation","Example: Tabs with Manual Activation","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties"
 "aria-setsize","0","3","Example: Infinite Scrolling Feed","Example: Treegrid Email Inbox","Example: File Directory Treeview  Using Declared Properties"
 "aria-sort","1","2","Guidance: Indicating sort order with aria-sort","Example: Data Grid","Example: Sortable Table"
 "aria-valuemax","1","8","Guidance: Using aria-valuemin, aria-valuemax and aria-valuenow","Example: Meter","Example: Horizontal Multi-Thumb Slider","Example: Color Viewer Slider","Example: Rating Slider","Example: Media Seek Slider","Example: Vertical Temperature Slider","Example: Date Picker Spin Button","Example: Toolbar"
diff --git a/content/about/coverage-and-quality/role-coverage.csv b/content/about/coverage-and-quality/role-coverage.csv
index 7652edde9c..cbebe3fb38 100644
--- a/content/about/coverage-and-quality/role-coverage.csv
+++ b/content/about/coverage-and-quality/role-coverage.csv
@@ -25,7 +25,7 @@
 "generic","0","0"
 "grid","3","5","Guidance: Grid Popup Keyboard Interaction","Guidance: Grid (Interactive Tabular Data and Layout Containers) Pattern","Guidance: Grid and Table Properties","Example: Date Picker Combobox","Example: Editable Combobox with Grid Popup","Example: Date Picker Dialog","Example: Data Grid","Example: Layout Grid"
 "gridcell","0","3","Example: Editable Combobox with Grid Popup","Example: Layout Grid","Example: Treegrid Email Inbox"
-"group","2","11","Guidance: Radio Group Pattern","Guidance: For Radio Group Contained in a Toolbar","Example: Auto-Rotating Image Carousel  with Buttons for Slide Control","Example: Checkbox  (Two State)","Example: Listbox  with Grouped Options","Example: Editor Menubar","Example: Color Viewer Slider","Example: Date Picker Spin Button","Example: Switch  Using HTML Button","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties","Example: Navigation Treeview"
+"group","2","10","Guidance: Radio Group Pattern","Guidance: For Radio Group Contained in a Toolbar","Example: Auto-Rotating Image Carousel  with Buttons for Slide Control","Example: Checkbox  (Two State)","Example: Listbox  with Grouped Options","Example: Editor Menubar","Example: Color Viewer Slider","Example: Date Picker Spin Button","Example: Switch  Using HTML Button","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: Navigation Treeview"
 "heading","0","0"
 "img","0","0"
 "input","0","0"
@@ -74,6 +74,6 @@
 "timer","0","0"
 "toolbar","3","1","Guidance: For Radio Groups Not Contained in a Toolbar","Guidance: For Radio Group Contained in a Toolbar","Guidance: Toolbar Pattern","Example: Toolbar"
 "tooltip","1","0","Guidance: Tooltip Pattern"
-"tree","2","4","Guidance: Tree Popup Keyboard Interaction","Guidance: Tree View Pattern","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties","Example: Navigation Treeview"
+"tree","2","3","Guidance: Tree Popup Keyboard Interaction","Guidance: Tree View Pattern","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: Navigation Treeview"
 "treegrid","1","1","Guidance: Treegrid Pattern","Example: Treegrid Email Inbox"
-"treeitem","0","4","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: [Experimental] File Directory Treeview  Using Computed Properties","Example: Navigation Treeview"
+"treeitem","0","3","Example: File Directory Treeview  Using Computed Properties","Example: File Directory Treeview  Using Declared Properties","Example: Navigation Treeview"
diff --git a/content/index/index.html b/content/index/index.html
index 1bce2ab871..c96c528253 100644
--- a/content/index/index.html
+++ b/content/index/index.html
@@ -907,8 +907,7 @@ <h2 id="examples_by_props_label">Examples By Properties and States</h2>
     <section id="examples_experimental">
       <h2 id="examples_experimental_label">Experimental Examples</h2>
       <div><strong>NOTE:</strong> The HC abbreviation means example has High Contrast support.</div>
-      <ul id="examples_experimental_ul">
-                <li><a href="../patterns/treeview/examples/treeview-1c.html">[Experimental] File Directory Treeview  Using Computed Properties</a></li></ul>
+      <ul id="examples_experimental_ul"></ul>
     </section>
   </main>
 
diff --git a/content/patterns/treeview/examples/treeview-1c.html b/content/patterns/treeview/examples/treeview-1c.html
deleted file mode 100644
index 555bf19257..0000000000
--- a/content/patterns/treeview/examples/treeview-1c.html
+++ /dev/null
@@ -1,432 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>[Experimental] File Directory Treeview Example Using Computed Properties</title>
-
-    <!-- Core JS and CSS shared by all examples -->
-    <link rel="stylesheet" href="https://www.w3.org/StyleSheets/TR/2016/base.css">
-    <link rel="stylesheet" href="../../../shared/css/core.css">
-    <script src="../../../shared/js/examples.js"></script>
-    <script src="../../../shared/js/utils.js"></script>
-    <script src="../../../shared/js/highlight.pack.js"></script>
-    <script src="../../../shared/js/app.js"></script>
-    <script data-skipto="colorTheme:aria; displayOption:popup; containerElement:div" src="../../../shared/js/skipto.js"></script>
-
-    <!-- JS and CSS for this example -->
-    <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.1.0/css/all.css" integrity="sha384-lKuwvrZot6UHsBSfcMvOkWwlCMgc0TaWr+30HWe3a4ltaBwTZhyTEggF5tJv8tbt" crossorigin="anonymous">
-    <link href="css/tree.css" rel="stylesheet">
-    <script src="js/tree.js"></script>
-    <script src="js/treeitem.js"></script>
-    <script src="js/treeitemClick.js"></script>
-  </head>
-  <body>
-    <nav aria-label="Related Links" class="feedback">
-      <ul>
-        <li><a href="https://github.com/w3c/aria-practices/projects/17">Related Issues</a></li>
-        <li><a href="../treeview-pattern.html">Design Pattern</a></li>
-      </ul>
-    </nav>
-    <main data-content-phase="experimental">
-      <h1>[Experimental] File Directory Treeview Example Using Computed Properties</h1>
-      <section>
-        <h2>About This Experimental Example</h2>
-        <img alt="" class="example-page-example-icon" src="../../../images/pattern-treeview.svg">
-        <p>
-          This experimental version of the File Directory Treeview Example Using Declared Properties example is not intended to ever be released or shown to the public. 
-          It exists merely to ensure that experimental content support can be adequately developed and tested.
-          When support is fully implemented, this example can be deleted.
-        </p>
-        <p>
-          This example relies on the browser to compute values for <code>aria-setsize</code>, <code>aria-posinset</code>, and <code>aria-level</code>.
-          The ARIA specification for these properties states that browsers can, but are not required to, compute their values.
-          So, some browser and assistive technology combinations may not compute or report correct position and level information if it is not explicitly declared.
-          If testing reveals gaps in support for these properties, override automatic computation by explicitly declaring their values as demonstrated in the example of a <a href="treeview-1b.html">File Directory Treeview using <em>declared</em> properties.</a>
-        </p>
-        <p>Similar examples include:</p>
-        <ul>
-          <li>
-            <a href="treeview-1b.html">File Directory Treeview using <em>declared</em> properties</a>
-          </li>
-          <li><a href="treeview-navigation.html">Navigation Treeview Example</a></li>
-        </ul>
-      </section>
-
-      <section>
-        <div class="example-header">
-          <h2 id="start">Experimental Example</h2>
-        </div>
-        <div role="separator" id="ex_start_sep" aria-labelledby="ex_start_sep start" aria-label="Start of"></div>
-        <div id="ex1">
-          <h3 id="tree_label">My Documents</h3>
-          <ul role="tree" aria-labelledby="tree_label">
-            <li role="treeitem" aria-expanded="false" aria-selected="false">
-              <span> Projects </span>
-              <ul role="group">
-                <li role="treeitem" aria-selected="false" class="doc">project-1.docx</li>
-                <li role="treeitem" aria-selected="false" class="doc">project-2.docx</li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> Project 3 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">project-3A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-3B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-3C.docx</li>
-                  </ul>
-                </li>
-                <li role="treeitem" aria-selected="false" class="doc">project-4.docx</li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> Project 5 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">project-5A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-5B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-5C.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-5D.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-5E.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">project-5F.docx</li>
-                  </ul>
-                </li>
-              </ul>
-            </li>
-            <li role="treeitem" aria-expanded="false" aria-selected="false">
-              <span> Reports </span>
-              <ul role="group">
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> report-1 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">report-1A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-1B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-1C.docx</li>
-                  </ul>
-                </li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> report-2 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">report-2A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-2B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-2C.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-2D.docx</li>
-                  </ul>
-                </li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> report-3 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">report-3A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-3B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-3C.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">report-3D.docx</li>
-                  </ul>
-                </li>
-              </ul>
-            </li>
-            <li role="treeitem" aria-expanded="false" aria-selected="false">
-              <span> Letters </span>
-              <ul role="group">
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> letter-1 </span>
-                  <ul>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-1A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-1B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-1C.docx</li>
-                  </ul>
-                </li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> letter-2 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">letter-2A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-2B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-2C.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-2D.docx</li>
-                  </ul>
-                </li>
-                <li role="treeitem" aria-expanded="false" aria-selected="false">
-                  <span> letter-3 </span>
-                  <ul role="group">
-                    <li role="treeitem" aria-selected="false" class="doc">letter-3A.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-3B.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-3C.docx</li>
-                    <li role="treeitem" aria-selected="false" class="doc">letter-3D.docx</li>
-                  </ul>
-                </li>
-              </ul>
-            </li>
-          </ul>
-
-          <p>
-            <label>File or Folder Selected: <input id="last_action" type="text" size="15" readonly></label>
-          </p>
-        </div>
-        <div role="separator" id="ex_end_sep" aria-labelledby="ex_end_sep start" aria-label="End of"></div>
-      </section>
-
-      <section>
-        <h2>Accessibility Features</h2>
-        <p>To make the focus indicator easier to see, nodes in the tree have custom focus and hover styling created using CSS focus and hover pseudo-classes.</p>
-      </section>
-
-      <section>
-        <h2>Terms Used to Describe Trees</h2>
-        <p>
-          A tree item that can be expanded to reveal child items is called a parent node.
-          It is a closed node when the children are hidden and an open node when it is expanded.
-          An end node does not have any children.
-          For a complete list of terms and definitions, see the <a href="../treeview-pattern.html#terms">Treeview Pattern</a>.
-        </p>
-      </section>
-
-      <section>
-        <h2 id="kbd_label">Keyboard Support</h2>
-        <p>
-          Note that in this example, selection and focus are distinct; moving focus does not change which node is selected.
-          Because selection does not follow focus, keyboard and screen reader users can navigate and explore the tree without changing the content of the file viewer.
-          To learn more about this aspect of the design, see
-          <a href="../../../practices/keyboard-interface/keyboard-interface-practice.html#kbd_selection_follows_focus">Deciding When to Make Selection Automatically Follow Focus</a>.
-        </p>
-        <table aria-labelledby="kbd_label" class="def">
-          <thead>
-            <tr>
-              <th>Key</th>
-              <th>Function</th>
-            </tr>
-          </thead>
-          <tbody>
-            <tr data-test-id="key-enter">
-              <th><kbd>Enter</kbd></th>
-              <td>Performs the default action, which is to select the node, causing the name of the node to appear in the <q>File or Folder Selected</q> textbox.</td>
-            </tr>
-            <tr data-test-id="key-space">
-              <th><kbd>Space</kbd></th>
-              <td>Performs the default action, which is to select the node, causing the name of the node to appear in the <q>File or Folder Selected</q> textbox.</td>
-            </tr>
-            <tr data-test-id="key-down-arrow">
-              <th><kbd>Down arrow</kbd></th>
-              <td>
-                <ul>
-                  <li>Moves focus to the next node that is focusable without opening or closing a node.</li>
-                  <li>If focus is on the last node, does nothing.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="key-up-arrow">
-              <th><kbd>Up arrow</kbd></th>
-              <td>
-                <ul>
-                  <li>Moves focus to the previous node that is focusable without opening or closing a node.</li>
-                  <li>If focus is on the first node, does nothing.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="key-right-arrow">
-              <th><kbd>Right Arrow</kbd></th>
-              <td>
-                <ul>
-                  <li>When focus is on a closed node, opens the node; focus does not move.</li>
-                  <li>When focus is on a open node, moves focus to the first child node.</li>
-                  <li>When focus is on an end node, does nothing.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="key-left-arrow">
-              <th><kbd>Left Arrow</kbd></th>
-              <td>
-                <ul>
-                  <li>When focus is on an open node, closes the node.</li>
-                  <li>When focus is on a child node that is also either an end node or a closed node, moves focus to its parent node.</li>
-                  <li>When focus is on a root node that is also either an end node or a closed node, does nothing.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="key-home">
-              <th><kbd>Home</kbd></th>
-              <td>Moves focus to first node without opening or closing a node.</td>
-            </tr>
-            <tr data-test-id="key-end">
-              <th><kbd>End</kbd></th>
-              <td>Moves focus to the last node that can be focused without expanding any nodes that are closed.</td>
-            </tr>
-            <tr data-test-id="key-character">
-              <th><kbd>a-z, A-Z</kbd></th>
-              <td>
-                <ul>
-                  <li>Focus moves to the next node with a name that starts with the typed character.</li>
-                  <li>Search wraps to first node if a matching name is not found among the nodes that follow the focused node.</li>
-                  <li>Search ignores nodes that are descendants of closed nodes.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="key-asterisk">
-              <th><kbd>*</kbd> (asterisk)</th>
-              <td>
-                <ul>
-                  <li>Expands all closed sibling nodes that are at the same level as the focused node.</li>
-                  <li>Focus does not move.</li>
-                </ul>
-              </td>
-            </tr>
-          </tbody>
-        </table>
-      </section>
-
-      <section>
-        <h2 id="rps_label">Role, Property, State, and Tabindex Attributes</h2>
-        <table aria-labelledby="rps_label" class="data attributes">
-          <thead>
-            <tr>
-              <th scope="col">Role</th>
-              <th scope="col">Attribute</th>
-              <th scope="col">Element</th>
-              <th scope="col">Usage</th>
-            </tr>
-          </thead>
-          <tbody>
-            <tr data-test-id="tree-role">
-              <th scope="row"><code>tree</code></th>
-              <td></td>
-              <td><code>ul</code></td>
-              <td>
-                <ul>
-                  <li>Identifies the <code>ul</code> element as a <code>tree</code> widget.</li>
-                  <li>
-                    The tree element is not focusable because it implements the practice described in
-                    <a href="../../../practices/keyboard-interface/keyboard-interface-practice.html#kbd_roving_tabindex">Managing Focus Within Components Using a Roving tabindex</a>.
-                  </li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="tree-aria-labelledby">
-              <td></td>
-              <th scope="row"><code>aria-labelledby="ID_REFERENCE"</code></th>
-              <td><code>ul</code></td>
-              <td>Refers to the heading element that contains the label that identifies the purpose of the <code>tree</code>.</td>
-            </tr>
-            <tr data-test-id="treeitem-role">
-              <th scope="row"><code>treeitem</code></th>
-              <td></td>
-              <td><code>li</code></td>
-              <td>Identifies the element as a <code>treeitem</code>.</td>
-            </tr>
-            <tr data-test-id="treeitem-tabindex">
-              <td></td>
-              <th scope="row"><code>tabindex="-1"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Makes the <code>treeitem</code> element focusable without including it in the tab sequence of the page.</li>
-                  <li>All <code>treeitem</code> elements are focusable, but only one is included in the tab sequence.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="treeitem-tabindex">
-              <td></td>
-              <th scope="row"><code>tabindex="0"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Includes the <code>treeitem</code> element in the tab sequence.</li>
-                  <li>Only one <code>treeitem</code> in the <code>tree</code> has <code>tabindex="0"</code>.</li>
-                  <li>In this implementation, the first <code>treeitem</code> in the <code>tree</code> is included in the tab sequence when the page loads.</li>
-                  <li>
-                    When the user moves focus in the <code>tree</code>, the element included in the tab sequence changes to the element with focus as described in
-                    <a href="../../../practices/keyboard-interface/keyboard-interface-practice.html#kbd_roving_tabindex">Managing Focus Within Components Using a Roving tabindex</a>.
-                  </li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="treeitem-aria-expanded">
-              <td></td>
-              <th scope="row"><code>aria-expanded="false"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Applied only to <code>treeitem</code> elements that are parent nodes, i.e., they contain a <code>ul</code> with the <code>group</code> role.</li>
-                  <li>Indicates the parent node is closed, i.e., the descendant elements are <strong>not</strong> visible.</li>
-                  <li>The visual indication of the collapsed state is synchronized by a CSS attribute selector.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="treeitem-aria-expanded">
-              <td></td>
-              <th scope="row"><code>aria-expanded="true"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Applied only to <code>treeitem</code> elements that are parent nodes, i.e., they contain a <code>ul</code> with the <code>group</code> role.</li>
-                  <li>Indicates the parent node is open, i.e., the descendant elements <strong>are</strong> visible.</li>
-                  <li>The visual indication of the expanded state is synchronized by a CSS attribute selector.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="treeitem-aria-selected">
-              <td></td>
-              <th scope="row"><code>aria-selected="false"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Applied to <code>treeitem</code> elements.</li>
-                  <li>Indicates the file or folder for the item is not currently selected.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="treeitem-aria-selected">
-              <td></td>
-              <th scope="row"><code>aria-selected="true"</code></th>
-              <td><code>li</code></td>
-              <td>
-                <ul>
-                  <li>Applied to <code>treeitem</code> elements.</li>
-                  <li>Indicates the file or folder for the item is currently selected.</li>
-                </ul>
-              </td>
-            </tr>
-            <tr data-test-id="group-role">
-              <th scope="row"><code>group</code></th>
-              <td></td>
-              <td><code>ul</code></td>
-              <td>
-                <ul>
-                  <li>Identifies the <code>ul</code> element as a container of <code>treeitem</code> elements that form a branch of the tree.</li>
-                  <li>The group is contained in the element that serves as the parent <code>treeitem</code>.</li>
-                  <li>Browsers use the grouping to compute <code>aria-level</code>, <code>aria-setsize</code> and <code>aria-posinset</code> values for the nodes contained in the branch.</li>
-                  <li>The grouping also prevents browsers from including the content of the nodes in the group in the accessible name for the parent node.</li>
-                </ul>
-              </td>
-            </tr>
-          </tbody>
-        </table>
-      </section>
-
-      <section>
-        <h2>JavaScript and CSS Source Code</h2>
-        <ul id="css_js_files">
-          <li>
-            CSS:
-            <a href="css/tree.css" type="text/css">tree.css</a>
-          </li>
-          <li>
-            Javascript:
-            <a href="js/tree.js" type="text/javascript">tree.js</a>
-          </li>
-          <li>
-            Javascript:
-            <a href="js/treeitem.js" type="text/javascript">treeitem.js</a>
-          </li>
-          <li>
-            Javascript:
-            <a href="js/treeitemClick.js" type="text/javascript">treeitemClick.js</a>
-          </li>
-        </ul>
-      </section>
-
-      <section>
-        <h2 id="sc1_label">HTML Source Code</h2>
-        <div role="separator" id="sc1_start_sep" aria-labelledby="sc1_start_sep sc1_label" aria-label="Start of"></div>
-        <pre><code id="sc1"></code></pre>
-        <div role="separator" id="sc1_end_sep" aria-labelledby="sc1_end_sep sc1_label" aria-label="End of"></div>
-        <script>
-          sourceCode.add('sc1', 'ex1', 'start', 'css_js_files');
-          sourceCode.make();
-        </script>
-      </section>
-    </main>
-  </body>
-</html>