diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control-expected.txt
index a2511f15a750..de3a0e73a4d7 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control-expected.txt
@@ -2,6 +2,61 @@ Tests the #comp_embedded_control portions of the AccName Name Computation algori
 
   Flash the screen   times
 
+  Flash the screen   times
+
+  Flash the screen   times
+
+  Flash the screen   times
+
+  Flash the screen 3 times
+
+  Flash the screen 3 times
+
+  Flash the screen
+1
+2
+3
+4
+5
+ times
+
+  Flash the screen   times
+
+  Flash the screen   times
+
+  Flash the screen 3.0 times
+
+  Flash the screen 3.0 times
+
+  Flash the screen 3.0 times
+
+  Flash the screen 3.0 times
+
+
 FAIL checkbox label with embedded textfield assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded textfield" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
 PASS label of embedded textfield inside checkbox label
+FAIL checkbox label with embedded select:not([size]) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded select:not([size])" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded select:not([size]) inside checkbox label
+FAIL checkbox label with embedded select[size] assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded select[size]" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded select[size] inside checkbox label
+FAIL checkbox label with embedded combobox (input[type=text]) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (input[type=text])" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded combobox (input[type=text]) inside checkbox label
+FAIL checkbox label with embedded combobox (span) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (span)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded combobox (span) inside checkbox label
+FAIL checkbox label with embedded combobox (div) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (div)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded combobox (div) inside checkbox label
+FAIL checkbox label with embedded listbox>option[aria-selected=true] assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded listbox>option[aria-selected=true]" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded listbox>option[aria-selected=true] inside checkbox label
+FAIL checkbox label with embedded input[type=range] assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded input[type=range]" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded input[type=range] inside checkbox label
+FAIL checkbox label with embedded input[type=number] assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded input[type=number]" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded input[type=number] inside checkbox label
+FAIL checkbox label with embedded ARIA slider (aria-valuenow) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA slider (aria-valuenow)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded ARIA slider (aria-valuenow) inside checkbox label
+FAIL checkbox label with embedded ARIA slider (aria-valuetext) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA slider (aria-valuetext)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded ARIA slider (aria-valuetext) inside checkbox label
+FAIL checkbox label with embedded ARIA spinbutton (aria-valuenow) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA spinbutton (aria-valuenow)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded ARIA spinbutton (aria-valuenow) inside checkbox label
+FAIL checkbox label with embedded ARIA spinbutton (aria-valuetext) assert_equals: <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA spinbutton (aria-valuetext)" class="ex"> expected "Flash the screen 3 times" but got "Flash the screen number of times times"
+PASS label of embedded ARIA spinbutton (aria-valuetext) inside checkbox label
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control.html
index 09856ef662e9..2cdb5cbdf7d0 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_embedded_control.html
@@ -13,24 +13,119 @@
 
 <p>Tests the <a href="https://w3c.github.io/accname/#comp_embedded_control">#comp_embedded_control</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
+<!-- Textfield (textbox) -->
 <label>
   <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded textfield" class="ex">
   Flash the screen
   <input value="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded textfield inside checkbox label" class="ex"> times
 </label>
+<br><br>
 
+<!-- HTML select:not([size]) element renders as menu button (on Mac) or single-row listbox (on Windows/Linux) -->
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded select:not([size])" class="ex">
+  Flash the screen
+  <select aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded select:not([size]) inside checkbox label" class="ex">
+    <option value="1">1</option>
+    <option value="2">2</option>
+    <option value="3" selected>3</option>
+    <option value="4">4</option>
+    <option value="5">5</option>
+  </select>
+  times
+</label>
+<br><br>
+
+<!-- HTML select[size] element renders as multi-row listbox -->
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded select[size]" class="ex">
+  Flash the screen
+  <select size=5 aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded select[size] inside checkbox label" class="ex">
+    <option value="1">1</option>
+    <option value="2">2</option>
+    <option value="3" selected>3</option>
+    <option value="4">4</option>
+    <option value="5">5</option>
+  </select>
+  times
+</label>
+<br><br>
+
+<!-- ARIA combobox examples (not interactive) -->
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (input[type=text])" class="ex">
+  Flash the screen
+  <input role="combobox" value="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded combobox (input[type=text]) inside checkbox label" class="ex"> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (span)" class="ex">
+  Flash the screen
+  <span role="combobox" tabindex="0" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded combobox (span) inside checkbox label" class="ex">3</span> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded combobox (div)" class="ex">
+  Flash the screen
+  <div style="display: inline-block;" role="combobox" tabindex="0" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded combobox (div) inside checkbox label" class="ex">3</div> times
+</label>
+<br><br>
+<!-- Todo: we may want another combobox example using aria-activedescendant? -->
+
+
+<!-- ARIA listbox examples (not interactive) -->
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded listbox>option[aria-selected=true]" class="ex">
+  Flash the screen
+  <ul role="listbox" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded listbox>option[aria-selected=true] inside checkbox label" class="ex" style="padding:0; list-style:none; border: solid 1px gray; width: 15em; display: inline-block;">
+    <li role="option" tabindex="-1" style="padding:0.2em 0.8em; list-style:none;">1</li>
+    <li role="option" tabindex="-1" style="padding:0.2em 0.8em; list-style:none;">2</li>
+    <li role="option" tabindex="0" aria-selected="true" style="padding:0.2em 0.8em; list-style:none; color: white; background-color: #555;">3</li>
+    <li role="option" tabindex="-1" style="padding:0.2em 0.8em; list-style:none;">4</li>
+    <li role="option" tabindex="-1" style="padding:0.2em 0.8em; list-style:none;">5</li>
+  </ul> times
+</label>
+<br><br>
 
-<!--
 
-Todo: test all remaining cases of https://w3c.github.io/accname/#comp_embedded_control
- - comp_embedded_control_textbox
- - comp_embedded_control_combobox_or_listbox
- - comp_embedded_control_range
- - comp_embedded_control_range_valuetext
- - comp_embedded_control_range_valuenow
- - comp_embedded_control_range_host_language_value
+<!-- Ranges: HTML native and ARIA sliders and steppers (valuetext, valuenow, host language specific) -->
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded input[type=range]" class="ex">
+  Flash the screen
+  <input type ="range" min="1" max="5" value="3" step="1" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded input[type=range] inside checkbox label" class="ex"> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded input[type=number]" class="ex">
+  Flash the screen
+  <input type ="number" min="1" max="5" value="3" step="1" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded input[type=number] inside checkbox label" class="ex"> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA slider (aria-valuenow)" class="ex">
+  Flash the screen
+  <span tabindex="0" role="slider" aria-valuemin="1" aria-valuemax="5" aria-valuenow="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded ARIA slider (aria-valuenow) inside checkbox label" class="ex">3.0</span> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA slider (aria-valuetext)" class="ex">
+  Flash the screen
+  <span tabindex="0" role="slider" aria-valuemin="1.0" aria-valuemax="5.0" aria-valuenow="3.0" aria-valuetext="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded ARIA slider (aria-valuetext) inside checkbox label" class="ex">3.0</span> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA spinbutton (aria-valuenow)" class="ex">
+  Flash the screen
+  <span tabindex="0" role="spinbutton" aria-valuemin="1" aria-valuemax="5" aria-valuenow="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded ARIA spinbutton (aria-valuenow) inside checkbox label" class="ex">3.0</span> times
+</label>
+<br><br>
+<label>
+  <input type="checkbox" data-expectedlabel="Flash the screen 3 times" data-testname="checkbox label with embedded ARIA spinbutton (aria-valuetext)" class="ex">
+  Flash the screen
+  <span tabindex="0" role="spinbutton" aria-valuemin="1.0" aria-valuemax="5.0" aria-valuenow="3.0" aria-valuetext="3" aria-label="number of times" data-expectedlabel="number of times" data-testname="label of embedded ARIA spinbutton (aria-valuetext) inside checkbox label" class="ex">3.0</span> times
+</label>
+<br><br>
 
--->
 
 <script>
 AriaUtils.verifyLabelsBySelector(".ex");
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced-expected.txt
index 37bf98b028eb..b37aa9818bf8 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced-expected.txt
@@ -1,7 +1,18 @@
 Tests the #comp_hidden_not_referenced portions of the AccName Name Computation algorithm.
 
-heading label
+hidden, visible to all users   hidden but referenced, visible to all users   hidden, visible to all users  visible to all users, hidden, hidden but referenced,
+visible to all users, un-hidden for all users
 
 
-PASS heading with interior hidden node
+PASS button containing a rendered, unreferenced element that is aria-hidden=true, an unreferenced element with the hidden host language attribute, and an unreferenced element that is unconditionally rendered
+PASS button labelled by element that is aria-hidden=true
+PASS button labelled by element with the hidden host language attribute
+PASS link labelled by elements with assorted visibility and a11y tree exposure
+FAIL heading with name from content, containing element that is visibility:hidden with nested content that is visibility:visible assert_equals: <h2 class="ex" data-testname="heading with name from content, containing element that is visibility:hidden with nested content that is visibility:visible" data-expectedlabel="visible to all users, un-hidden for all users">
+  visible to all users,
+  <span style="visibility: hidden;">
+    hidden from all users,
+    <span style="visibility: visible;">un-hidden for all users</span>
+  </span>
+</h2> expected "visible to all users, un-hidden for all users" but got "visible to all users,"
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced.html
index 84a2a2ca8026..7d9cf2c36f64 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_hidden_not_referenced.html
@@ -1,6 +1,7 @@
 <!doctype html>
 <html>
 <head>
+  <meta charset="utf-8">
   <title>Name Comp: Hidden Not Referenced</title>
   <script src="/resources/testharness.js"></script>
   <script src="/resources/testharnessreport.js"></script>
@@ -13,16 +14,79 @@
 
 <p>Tests the <a href="https://w3c.github.io/accname/#comp_hidden_not_referenced">#comp_hidden_not_referenced</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
-<h2 class="ex" data-expectedlabel="heading label" data-testname="heading with interior hidden node">
-  heading
-  <span hidden>bogus</span>
-  label
+<button
+  class="ex"
+  data-expectedlabel="visible to all users"
+  data-testname="button containing a rendered, unreferenced element that is aria-hidden=true, an unreferenced element with the hidden host language attribute, and an unreferenced element that is unconditionally rendered"
+>
+  <span aria-hidden="true">hidden,</span>
+  <span hidden>hidden from all users,</span>
+  <span>visible to all users</span>
+</button>
+
+<button
+  class="ex"
+  data-expectedlabel="hidden but referenced,"
+  data-testname="button labelled by element that is aria-hidden=true"
+  aria-labelledby="button-label-2"
+>
+  <span aria-hidden="true" id="button-label-2">hidden but referenced,</span>
+  <span hidden>hidden from all users,</span>
+  <span>visible to all users</span>
+</button>
+
+<button
+  class="ex"
+  data-expectedlabel="hidden from all users but referenced,"
+  data-testname="button labelled by element with the hidden host language attribute"
+  aria-labelledby="button-label-3"
+>
+  <span aria-hidden="true">hidden,</span>
+  <span hidden id="button-label-3">hidden from all users but referenced,</span>
+  <span>visible to all users</span>
+</button>
+
+<a
+  class="ex"
+  data-testname="link labelled by elements with assorted visibility and a11y tree exposure"
+  data-expectedlabel="visible to all users, hidden but referenced, hidden from all users but referenced"
+  href="#"
+  aria-labelledby="link-label-1a link-label-1b link-label-1c"
+>
+  <span id="link-label-1a">
+    <span>visible to all users,</span>
+    <span aria-hidden="true">hidden,</span>
+  </span>
+  <span aria-hidden="true" id="link-label-1b">hidden but referenced,</span>
+  <span hidden id="link-label-1c">hidden from all users but referenced</span>
+</a>
+
+<h2
+  class="ex"
+  data-testname="heading with name from content, containing element that is visibility:hidden with nested content that is visibility:visible"
+  data-expectedlabel="visible to all users, un-hidden for all users"
+>
+  visible to all users,
+  <span style="visibility: hidden;">
+    hidden from all users,
+    <span style="visibility: visible;">un-hidden for all users</span>
+  </span>
 </h2>
 
-<!-- Todo: test all remaining cases of https://w3c.github.io/accname/#comp_hidden_not_referenced -->
+<!-- TODO: Test cases once https://github.com/w3c/aria/issues/1256 resolved: -->
+<!--       - button labelled by an element that is aria-hidden=true which contains a nested child that is aria-hidden=false -->
+<!--       - button labelled by an element that is aria-hidden=false which belongs to a parent that is aria-hidden=true -->
+<!--       - heading with name from content, containing rendered content that is aria-hidden=true with nested, rendered content that is aria-hidden=false -->
+<!--       - heading with name from content, containing element with the hidden host language attribute with nested content that is aria-hidden=false -->
+
+<!-- TODO: New test case?
+<!--       What is the expectation for a details element when it’s given an -->
+<!--       explicit role that allows name from contents (e.g., `comment`) -->
+<!--       but is also not in the open state, and therefore has contents -->
+<!--       that are both not rendered and excluded from the a11y tree. -->
 
 <script>
 AriaUtils.verifyLabelsBySelector(".ex");
 </script>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_host_language_label-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_host_language_label-expected.txt
index 23ee626b29f3..5c4146a187ea 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_host_language_label-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_host_language_label-expected.txt
@@ -85,7 +85,7 @@ PASS html: label[for] input[type=week]
 PASS html: label input[type=checkbox] encapsulation
 PASS html: label input[type=color] encapsulation
 FAIL html: label input[type=date] encapsulation assert_equals: <input type="date" data-expectedlabel="date label" data-testname="html: label input[type=date] encapsulation" class="ex"> expected "date label" but got "month / day / year date label"
-FAIL html: label input[type=datetime-local] encapsulation assert_equals: <input type="datetime-local" data-expectedlabel="datetime-local label" data-testname="html: label input[type=datetime-local] encapsulation" class="ex"> expected "datetime-local label" but got "month / day / year , 12 : 30 PM datetime-local label"
+FAIL html: label input[type=datetime-local] encapsulation assert_equals: <input type="datetime-local" data-expectedlabel="datetime-local label" data-testname="html: label input[type=datetime-local] encapsulation" class="ex"> expected "datetime-local label" but got "month / day / year , 12 : 30   PM datetime-local label"
 PASS html: label input[type=email] encapsulation
 FAIL html: label input[type=month] encapsulation assert_equals: <input type="month" data-expectedlabel="month label" data-testname="html: label input[type=month] encapsulation" class="ex"> expected "month label" but got "month / year month label"
 PASS html: label input[type=number] encapsulation
@@ -95,7 +95,7 @@ FAIL html: label input[type=range] encapsulation assert_equals: <input type="ran
 FAIL html: label input[type=search] encapsulation assert_equals: <input type="search" data-expectedlabel="search label" data-testname="html: label input[type=search] encapsulation" class="ex"> expected "search label" but got "cancel search label"
 PASS html: label input[type=tel] encapsulation
 PASS html: label[for] input[type=text] encapsulation
-FAIL html: label input[type=time] encapsulation assert_equals: <input type="time" data-expectedlabel="time label" data-testname="html: label input[type=time] encapsulation" class="ex"> expected "time label" but got "12 : 30 PM time label"
+FAIL html: label input[type=time] encapsulation assert_equals: <input type="time" data-expectedlabel="time label" data-testname="html: label input[type=time] encapsulation" class="ex"> expected "time label" but got "12 : 30   PM time label"
 PASS html: label input[type=url] encapsulation
 PASS html: label input[type=week] encapsulation
 PASS html: select for/id
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby-expected.txt
index dabaf7a23a50..599525d3b463 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby-expected.txt
@@ -1,9 +1,16 @@
 Tests the #comp_labelledby portions of the AccName Name Computation algorithm.
 
-div group label
+first heading
 
 text inside div group
 
++ first heading
+
+text inside div group
+
+verifyspacesFAIL IF INCLUDEDbetweenforeach
 
 PASS div group explicitly labelledby heading
+PASS div group explicitly labelledby self and heading
+PASS nav with verified spaces appended between each of IDREFS
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby.html
index ab17bff11874..2a22fd891912 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_labelledby.html
@@ -13,14 +13,37 @@
 
 <p>Tests the <a href="https://w3c.github.io/accname/#comp_labelledby">#comp_labelledby</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
-<div role="group" aria-labelledby="h" class="ex" data-expectedlabel="div group label" data-testname="div group explicitly labelledby heading">
-  <h2 id="h">div group label</h2>
+<!--
+
+  Some overlap with other aria-labelledby tests in:
+  - /accname/name/comp_label.html (aria-labelledby / aria-label fallback, etc.)
+  - /accname/name/comp_name_from_content.html
+  - /accname/name/shadowdom/*
+
+-->
+
+<div role="group" aria-labelledby="h" class="ex" data-expectedlabel="first heading" data-testname="div group explicitly labelledby heading">
+  <h2 id="h">first heading</h2>
   <p>text inside div group</p>
 </div>
 
+<div role="group" aria-label="self label" id="g2" aria-labelledby="g2 h2" class="ex" data-expectedlabel="self label + first heading" data-testname="div group explicitly labelledby self and heading">
+  <h2 id="h2">+ first heading</h2>
+  <p>text inside div group</p>
+</div>
+
+<nav aria-labelledby="s1 s2 s3 s4" class="ex" data-expectedlabel="verify spaces between foreach" data-testname="nav with verified spaces appended between each of IDREFS">
+  <span id="s1">verify</span><span id="s2">spaces</span><span>FAIL IF INCLUDED</span><span id="s3">between</span><span id="s4">foreach</span>
+</nav>
+
 <!--
 
-Todo: test all remaining cases of https://w3c.github.io/accname/#comp_labelledby
+  BLOCKED on https://github.com/w3c/accname/issues/209
+
+  Once that's resolved, it may be worthwhile to add a new ./comp_labelledby_recursion.html file,
+  so that the implementation diffs rolling in don't penalize this Interop 2024 test.
+
+  All remaining cases of https://w3c.github.io/accname/#comp_labelledby
   - comp_labelledby_reset
   - comp_labelledby_foreach
   - comp_labelledby_set_current
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content-expected.txt
index e4175b9e0b93..a2c5060f6c91 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content-expected.txt
@@ -1,7 +1,229 @@
 Tests the #comp_name_from_content portions of the AccName Name Computation algorithm.
 
+This series of tests exercises the button, heading, and link elements, because each have different characteristics worthy of testing in each of the name computation algorithm scenarios:
+
+button is a leaf node with sub-level elements presentational.
+heading is block level, and can contain sub-level interactives like links.
+link (a[href]) is an interactive inline element that can include non-presentational descendants.
+ARIA roles, inline
+
+label
+label
+label
+
+ARIA roles, block
+
+label
+label
+label
+
+simple
+
+label
+label
+
 label
 
+simple with ::before
+
+label
+label
+
+label
+
+simple with ::after
+
+label
+label
+
+label
+
+simple with ::before and ::after
+
+label
+label
+
+label
+
+no space joiners ::before and ::after
+
+label
+label
+
+label
+
+Arabic right-to-left (RTL) with ::before and ::after
+
+اسم
+اسم
+
+اسم
+
+Alternative Text for CSS content (previously `alt:`) in pseudo-elements
+
+rendered text should be "before label after"
+
+accessibility label should be "alt-before label alt-after"
+
+label
+label
+
+label
+
+simple w/ for each child
+
+one two three
+one two three
+
+one two three
+
+simple for each child with image
+
+one  three
+one  three
+
+one  three
+
+simple for each child with extra nesting containing image
+
+one two  four
+one two  four
+
+one two  four
+
+heading with nested button with nested image
+
+heading  button   button  heading
+
+heading with nested link with nested image
+
+heading link   link heading
+
+heading with nested link with nested image using aria-label
+
+heading ignored link text   ignored link text heading
+
+heading with nested link with nested image using aria-labelledby
+
+heading ignored link text   ignored link text heading
+
+heading with two nested links referencing image using aria-labelledby
+
+link1 link2   link3
+
+heading with link referencing image using aria-labelledby, that in turn references text element via aria-labelledby
+
+link
+
+heading with link referencing image using aria-labelledby, that in turn references itself and another element via aria-labelledby
+
+link
+
+simple w/ for each child (w/o spaces and display:inline)
+
+onetwothree
+onetwothree
+
+onetwothree
+
+simple w/ for each child (w/o spaces and display:block)
+
+
+one
+two
+three
+
+one
+two
+three
+
+one
+two
+three
+
+
+simple w/ for each child (w/o spaces and display:inline block)
+
+onetwothree
+onetwothree
+
+onetwothree
+
 
+PASS aria button name from content, inline
+PASS aria heading name from content, inline
+PASS aria link name from content, inline
+PASS aria button name from content, block
+PASS aria heading name from content, block
+PASS aria link name from content, block
+PASS button name from content
 PASS heading name from content
+PASS link name from content
+PASS button name from content with ::before
+PASS heading name from content with ::before
+PASS link name from content with ::before
+PASS button name from content with ::after
+PASS heading name from content with ::after
+PASS link name from content with ::after
+PASS button name from content with ::before and ::after
+PASS heading name from content with ::before and ::after
+PASS link name from content with ::before and ::after
+FAIL button name from content no space joiners ::before and ::after assert_equals: <button data-expectedlabel="nospacelabelnospace" data-testname="button name from content no space joiners ::before and ::after" class="ex no-space">label</button> expected "nospacelabelnospace" but got "nospace label nospace"
+FAIL heading name from content no space joiners ::before and ::after assert_equals: <h3 data-expectedlabel="nospacelabelnospace" data-testname="heading name from content no space joiners ::before and ::after" class="ex no-space">label</h3> expected "nospacelabelnospace" but got "nospace label nospace"
+FAIL link name from content no space joiners ::before and ::after assert_equals: <a href="#" data-expectedlabel="nospacelabelnospace" data-testname="link name from content no space joiners ::before and ::after" class="ex no-space">label</a> expected "nospacelabelnospace" but got "nospace label nospace"
+PASS button name from content with ::before and ::after in rtl
+PASS heading name from content with ::before and ::after in rtl
+PASS link name from content with ::before and ::after in rtl
+FAIL button name from fallback content with ::before and ::after assert_equals: <button data-expectedlabel="alt-before label alt-after" data-testname="button name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</button> expected "alt-before label alt-after" but got "before label after"
+FAIL heading name from fallback content with ::before and ::after assert_equals: <h3 data-expectedlabel="alt-before label alt-after" data-testname="heading name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</h3> expected "alt-before label alt-after" but got "before label after"
+FAIL link name from fallback content with ::before and ::after assert_equals: <a href="#" data-expectedlabel="alt-before label alt-after" data-testname="link name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</a> expected "alt-before label alt-after" but got "before label after"
+PASS button name from content for each child
+PASS heading name from content for each child
+PASS link name from content for each child
+PASS button name from content for each child including image
+PASS heading name from content for each child including image
+PASS link name from content for each child including image
+PASS button name from content for each child including nested image
+PASS heading name from content for each child including nested image
+PASS link name from content for each child including nested image
+PASS heading name from content for each child including nested button with nested image
+PASS heading name from content for each child including nested link with nested image
+PASS heading name from content for each child including nested link using aria-label with nested image
+PASS heading name from content for each child including nested link using aria-labelledby with nested image
+FAIL heading name from content for each child including two nested links using aria-labelledby with nested image assert_equals: <h3 data-expectedlabel="image link2 link3" data-testname="heading name from content for each child including two nested links using aria-labelledby with nested image" class="ex">
+  <a href="#" aria-labelledby="nested_image_label2">
+    link1<!-- this text is skipped because of aria-labelledby -->
+  </a>
+  <a href="#" data-expectedlabel="link2 image link3" data-testname="link name from content for each child including nested image (referenced elsewhere via labelledby)" class="ex">
+    link2
+    <img id="nested_image_label2" src="#" alt="image">
+    <!-- image skipped in this link (when computing heading text) because it was already referenced by the first link within this heading label recursion cycle. -->
+    <!-- but image not skipped when computing the text of the link itself since it has not been referenced in that context -->
+    link3
+  </a>
+</h3> expected "image link2 link3" but got "image link2 image link3"
+PASS link name from content for each child including nested image (referenced elsewhere via labelledby)
+FAIL heading with link referencing image using aria-labelledby, that in turn references text element via aria-labelledby assert_equals: <h3 data-expectedlabel="image link" data-testname="heading with link referencing image using aria-labelledby, that in turn references text element via aria-labelledby" class="ex">
+  <a href="#" aria-labelledby="nested_image_label3">
+    <span class="note" id="crossref_link">link</span><!-- this text is skipped the first time around because of aria-labelledby on parent element -->
+  </a>
+  <!-- but it's picked up again in inverse order b/c of cross-referencial aria-labelledby edge case -->
+  <img id="nested_image_label_3" src="#" alt="image" aria-labelledby="crossref_link">
+</h3> expected "image link" but got "link link"
+FAIL heading with link referencing image using aria-labelledby, that in turn references itself and another element via aria-labelledby assert_equals: <h3 data-expectedlabel="image link" data-testname="heading with link referencing image using aria-labelledby, that in turn references itself and another element via aria-labelledby" class="ex">
+  <a href="#" aria-labelledby="nested_image_label4">
+    <span class="note" id="crossref_link2">link</span><!-- this text is skipped the first time around because of aria-labelledby on parent element -->
+  </a>
+  <!-- but it's picked up again (after the self-referencial image alt) in inverse order b/c of cross-referencial aria-labelledby edge case -->
+  <img id="nested_image_label4" src="#" alt="image" aria-labelledby="nested_image_label4 crossref_link2">
+</h3> expected "image link" but got "image image link"
+FAIL button name from content for each child (no space, inline) assert_equals: <button data-expectedlabel="onetwothree" data-testname="button name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></button> expected "onetwothree" but got "one two three"
+FAIL heading name from content for each child (no space, inline) assert_equals: <h3 data-expectedlabel="onetwothree" data-testname="heading name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></h3> expected "onetwothree" but got "one two three"
+FAIL link name from content for each child (no space, inline) assert_equals: <a href="#" data-expectedlabel="onetwothree" data-testname="link name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></a> expected "onetwothree" but got "one two three"
+PASS button name from content for each child (no space, display:block)
+PASS heading name from content for each child (no space, display:block)
+PASS link name from content for each child (no space, display:block)
+PASS button name from content for each child (no space, display:inline-block)
+PASS heading name from content for each child (no space, display:inline-block)
+PASS link name from content for each child (no space, display:inline-block)
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content.html
index 0b40206a7ebc..41cd3506ce20 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_name_from_content.html
@@ -2,35 +2,251 @@
 <html>
 <head>
   <title>Name Comp: Name From Content</title>
+  <meta charset="utf-8">
   <script src="/resources/testharness.js"></script>
   <script src="/resources/testharnessreport.js"></script>
   <script src="/resources/testdriver.js"></script>
   <script src="/resources/testdriver-vendor.js"></script>
   <script src="/resources/testdriver-actions.js"></script>
   <script src="/wai-aria/scripts/aria-utils.js"></script>
+  <style type="text/css">
+
+     /*
+
+      Since the AccName spec is in flux about whitespace joiners, and the implementations don't match,
+      normalize the whitespace (with extra leading/trailing) space.
+
+      No point in having the same in-flux spec change cause failures the remaining unrelated tests.
+
+      See more here:
+      https://github.com/w3c/accname/issues/205
+      https://github.com/w3c/accname/projects/1#card-42288231
+
+    */
+
+    .simple-before::before {
+      content: " before "; /* [sic] leading and trailing space */
+      margin:0 0.1em;
+    }
+    .simple-after::after {
+      content: " after "; /* [sic] leading and trailing space */
+      margin:0 0.1em;
+    }
+    .no-space::before, .no-space::after {
+      content: "nospace"; /* [sic] Unlike the others, NO extra leading/trailing space here. */
+    }
+    .simple-before:dir(rtl)::before {
+      content: " من قبل "; /* [sic] leading and trailing space */
+    }
+    .simple-after:dir(rtl)::after {
+      content: " بعد "; /* [sic] leading and trailing space */
+    }
+    .fallback-before::before {
+      content: " before "; /* [sic] leading and trailing space */
+      content: " before " / " alt-before "; /* Override the previous line for engines that support the Alternative Text syntax. */
+    }
+    .fallback-after::after {
+      content: " after "; /* [sic] leading and trailing space */
+      content: " after " / " alt-after "; /* Override the previous line for engines that support the Alternative Text syntax. */
+    }
+    .block > span {
+      display: block;
+      margin: 0 0.1em;
+    }
+    .iblock > span {
+      display: inline-block;
+      margin: 0 0.1em;
+    }
+
+  </style>
 </head>
 <body>
 
 <p>Tests the <a href="https://w3c.github.io/accname/#comp_name_from_content">#comp_name_from_content</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
-<h1 data-expectedlabel="label" data-testname="heading name from content" class="ex">label</h1>
+<p>This series of tests exercises the button, heading, and link elements, because each have different characteristics worthy of testing in each of the name computation algorithm scenarios:</p>
+<ul>
+  <li>button is a leaf node with sub-level elements presentational.</li>
+  <li>heading is block level, and can contain sub-level interactives like links.</li>
+  <li>link (a[href]) is an interactive inline element that can include non-presentational descendants.</li>
+</ul>
+
+<h1>ARIA roles, inline</h1>
+<span tabindex="0" role="button" data-expectedlabel="label" data-testname="aria button name from content, inline" class="ex">label</span><br>
+<span tabindex="0" role="heading" data-expectedlabel="label" data-testname="aria heading name from content, inline" class="ex">label</span><br>
+<span tabindex="0" role="link" data-expectedlabel="label" data-testname="aria link name from content, inline" class="ex">label</span><br>
+<br>
+
+<h1>ARIA roles, block</h1>
+<div tabindex="0" role="button" data-expectedlabel="label" data-testname="aria button name from content, block" class="ex">label</div>
+<div tabindex="0" role="heading" data-expectedlabel="label" data-testname="aria heading name from content, block" class="ex">label</div>
+<div tabindex="0" role="link" data-expectedlabel="label" data-testname="aria link name from content, block" class="ex">label</div>
+<br>
+
+<h1>simple</h1>
+<button data-expectedlabel="label" data-testname="button name from content" class="ex">label</button><br>
+<h3 data-expectedlabel="label" data-testname="heading name from content" class="ex">label</h3>
+<a href="#" data-expectedlabel="label" data-testname="link name from content" class="ex">label</a><br>
+<br>
+
+<h1>simple with ::before</h1>
+<button data-expectedlabel="before label" data-testname="button name from content with ::before" class="ex simple-before">label</button><br>
+<h3 data-expectedlabel="before label" data-testname="heading name from content with ::before" class="ex simple-before">label</h3>
+<a href="#" data-expectedlabel="before label" data-testname="link name from content with ::before" class="ex simple-before">label</a><br>
+<br>
+
+<h1>simple with ::after</h1>
+<button data-expectedlabel="label after" data-testname="button name from content with ::after" class="ex simple-after">label</button><br>
+<h3 data-expectedlabel="label after" data-testname="heading name from content with ::after" class="ex simple-after">label</h3>
+<a href="#" data-expectedlabel="label after" data-testname="link name from content with ::after" class="ex simple-after">label</a><br>
+<br>
+
+<h1>simple with ::before and ::after</h1>
+<button data-expectedlabel="before label after" data-testname="button name from content with ::before and ::after" class="ex simple-before simple-after">label</button><br>
+<h3 data-expectedlabel="before label after" data-testname="heading name from content with ::before and ::after" class="ex simple-before simple-after">label</h3>
+<a href="#" data-expectedlabel="before label after" data-testname="link name from content with ::before and ::after" class="ex simple-before simple-after">label</a><br>
+<br>
+
+<h1>no space joiners ::before and ::after</h1>
+<button data-expectedlabel="nospacelabelnospace" data-testname="button name from content no space joiners ::before and ::after" class="ex no-space">label</button><br>
+<h3 data-expectedlabel="nospacelabelnospace" data-testname="heading name from content no space joiners ::before and ::after" class="ex no-space">label</h3>
+<a href="#" data-expectedlabel="nospacelabelnospace" data-testname="link name from content no space joiners ::before and ::after" class="ex no-space">label</a><br>
+<br>
+
+<h1>Arabic right-to-left (RTL) with ::before and ::after</h1>
+<div dir="rtl" lang="ar">
+  <button data-expectedlabel="من قبل اسم بعد" data-testname="button name from content with ::before and ::after in rtl" class="ex simple-before simple-after">اسم</button><br>
+  <h3 data-expectedlabel="من قبل اسم بعد" data-testname="heading name from content with ::before and ::after in rtl" class="ex simple-before simple-after">اسم</h3>
+  <a href="#" data-expectedlabel="من قبل اسم بعد" data-testname="link name from content with ::before and ::after in rtl" class="ex simple-before simple-after">اسم</a><br>
+</div>
+<br>
+
+<h1><a href="https://drafts.csswg.org/css-content/#alt">Alternative Text for  CSS content (previously `alt:`)</a> in pseudo-elements</h1>
+<p>rendered text should be "before label after"</p>
+<p>accessibility label should be "alt-before label alt-after"</p>
+<button data-expectedlabel="alt-before label alt-after" data-testname="button name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</button><br>
+<h3 data-expectedlabel="alt-before label alt-after" data-testname="heading name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</h3>
+<a href="#" data-expectedlabel="alt-before label alt-after" data-testname="link name from fallback content with ::before and ::after" class="ex fallback-before fallback-after">label</a><br>
+<br>
+
+<h1>simple w/ for each child</h1>
+<button data-expectedlabel="one two three" data-testname="button name from content for each child" class="ex"><span>one</span> <span>two</span> <span>three</span></button><br>
+<h3 data-expectedlabel="one two three" data-testname="heading name from content for each child" class="ex"><span>one</span> <span>two</span> <span>three</span></h3>
+<a href="#" data-expectedlabel="one two three" data-testname="link name from content for each child" class="ex"><span>one</span> <span>two</span> <span>three</span></a><br>
+<br>
+
+<h1>simple for each child with image</h1>
+<button data-expectedlabel="one two three" data-testname="button name from content for each child including image" class="ex"><span>one</span> <img src="#" alt="two"> <span>three</span></button><br>
+<h3 data-expectedlabel="one two three" data-testname="heading name from content for each child including image" class="ex"><span>one</span> <img src="#" alt="two"> <span>three</span></h3>
+<a href="#" data-expectedlabel="one two three" data-testname="link name from content for each child including image" class="ex"><span>one</span> <img src="#" alt="two"> <span>three</span></a><br>
+<br>
+
+
+<h1>simple for each child with extra nesting containing image</h1>
+<button data-expectedlabel="one two three four" data-testname="button name from content for each child including nested image" class="ex"><span>one</span> <span>two <img src="#" alt="three"></span> <span>four</span></button><br>
+<h3 data-expectedlabel="one two three four" data-testname="heading name from content for each child including nested image" class="ex"><span>one</span> <span>two <img src="#" alt="three"></span> <span>four</span></h3>
+<a href="#" data-expectedlabel="one two three four" data-testname="link name from content for each child including nested image" class="ex"><span>one</span> <span>two <img src="#" alt="three"></span> <span>four</span></a><br>
+<br>
+
+<h1>heading with nested button with nested image</h1>
+<h3 data-expectedlabel="heading button image button heading" data-testname="heading name from content for each child including nested button with nested image" class="ex">
+  heading
+  <button>
+    button
+    <img src="#" alt="image">
+    button
+  </button>
+  heading
+</h3>
+
+<h1>heading with nested link with nested image</h1>
+<h3 data-expectedlabel="heading link image link heading" data-testname="heading name from content for each child including nested link with nested image" class="ex">
+  heading
+  <a href="#">
+    link
+    <img src="#" alt="image">
+    link
+  </a>
+  heading
+</h3>
+
+<h1>heading with nested link with nested image using aria-label</h1>
+<h3 data-expectedlabel="heading link aria-label heading" data-testname="heading name from content for each child including nested link using aria-label with nested image" class="ex">
+  heading
+  <a href="#" aria-label="link aria-label"><!-- should skip the other link text -->
+    ignored link text
+    <img id="nested_image_label_1" src="#" alt="ignored image alt">
+    ignored link text
+  </a>
+  heading
+</h3>
+
+<h1>heading with nested link with nested image using aria-labelledby</h1>
+<h3 data-expectedlabel="heading image heading" data-testname="heading name from content for each child including nested link using aria-labelledby with nested image" class="ex">
+  heading
+  <a href="#" aria-labelledby="nested_image_label1"><!-- should skip the other link text -->
+    ignored link text
+    <img id="nested_image_label1" src="#" alt="image">
+    ignored link text
+  </a>
+  heading
+</h3>
+
+<h1>heading with two nested links referencing image using aria-labelledby</h1>
+<h3 data-expectedlabel="image link2 link3" data-testname="heading name from content for each child including two nested links using aria-labelledby with nested image" class="ex">
+  <a href="#" aria-labelledby="nested_image_label2">
+    link1<!-- this text is skipped because of aria-labelledby -->
+  </a>
+  <a href="#" data-expectedlabel="link2 image link3" data-testname="link name from content for each child including nested image (referenced elsewhere via labelledby)" class="ex">
+    link2
+    <img id="nested_image_label2" src="#" alt="image">
+    <!-- image skipped in this link (when computing heading text) because it was already referenced by the first link within this heading label recursion cycle. -->
+    <!-- but image not skipped when computing the text of the link itself since it has not been referenced in that context -->
+    link3
+  </a>
+</h3>
+
+<!-- cross-referencial edge case-->
+<h1>heading with link referencing image using aria-labelledby, that in turn references text element via aria-labelledby</h1>
+<h3 data-expectedlabel="image link" data-testname="heading with link referencing image using aria-labelledby, that in turn references text element via aria-labelledby" class="ex">
+  <a href="#" aria-labelledby="nested_image_label3">
+    <span class="note" id="crossref_link">link</span><!-- this text is skipped the first time around because of aria-labelledby on parent element -->
+  </a>
+  <!-- but it's picked up again in inverse order b/c of cross-referencial aria-labelledby edge case -->
+  <img id="nested_image_label_3" src="#" alt="image" aria-labelledby="crossref_link">
+</h3>
+
+<!-- self-referencial edge case-->
+<h1>heading with link referencing image using aria-labelledby, that in turn references itself and another element via aria-labelledby</h1>
+<h3 data-expectedlabel="image link" data-testname="heading with link referencing image using aria-labelledby, that in turn references itself and another element via aria-labelledby" class="ex">
+  <a href="#" aria-labelledby="nested_image_label4">
+    <span class="note" id="crossref_link2">link</span><!-- this text is skipped the first time around because of aria-labelledby on parent element -->
+  </a>
+  <!-- but it's picked up again (after the self-referencial image alt) in inverse order b/c of cross-referencial aria-labelledby edge case -->
+  <img id="nested_image_label4" src="#" alt="image" aria-labelledby="nested_image_label4 crossref_link2">
+</h3>
 
-<!--
 
-Todo: test all remaining cases of https://w3c.github.io/accname/#comp_name_from_content
-  - comp_name_from_content_reset
-  - comp_name_from_content_pseudo_element
-  - comp_name_from_content_pseudo_element_before
-  - comp_name_from_content_pseudo_element_after
-  - comp_name_from_content_for_each_child
-  - comp_name_from_content_for_each_child_set_current
-  - comp_name_from_content_for_each_child_recursion
-  - comp_for_each_child_append
-  - comp_name_from_content_return
+<!-- Note: The following test is out of line with the spec, but matching two out of three implementations at the time of writing, and spec changes are expeected. -->
+<!-- See details in https://github.com/w3c/accname/issues/205 -->
+<!-- Final spec resolution will be addressed in AccName Whitespace Project: https://github.com/w3c/accname/projects/1#card-42288231 -->
+<h1>simple w/ for each child (w/o spaces and display:inline)</h1>
+<button data-expectedlabel="onetwothree" data-testname="button name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></button><br>
+<h3 data-expectedlabel="onetwothree" data-testname="heading name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></h3>
+<a href="#" data-expectedlabel="onetwothree" data-testname="link name from content for each child (no space, inline)" class="ex"><span>one</span><span>two</span><span>three</span></a><br>
+<br>
 
-Todo: test all remaining *recursive* cases in https://w3c.github.io/accname/#comp_recursive_name_from_content
+<h1>simple w/ for each child (w/o spaces and display:block)</h1>
+<button data-expectedlabel="one two three" data-testname="button name from content for each child (no space, display:block)" class="ex block"><span>one</span><span>two</span><span>three</span></button><br>
+<h3 data-expectedlabel="one two three" data-testname="heading name from content for each child (no space, display:block)" class="ex block"><span>one</span><span>two</span><span>three</span></h3>
+<a href="#" data-expectedlabel="one two three" data-testname="link name from content for each child (no space, display:block)" class="ex block"><span>one</span><span>two</span><span>three</span></a><br>
+<br>
 
--->
+<h1>simple w/ for each child (w/o spaces and display:inline block)</h1>
+<button data-expectedlabel="one two three" data-testname="button name from content for each child (no space, display:inline-block)" class="ex iblock"><span>one</span><span>two</span><span>three</span></button><br>
+<h3 data-expectedlabel="one two three" data-testname="heading name from content for each child (no space, display:inline-block)" class="ex iblock"><span>one</span><span>two</span><span>three</span></h3>
+<a href="#" data-expectedlabel="one two three" data-testname="link name from content for each child (no space, display:inline-block)" class="ex iblock"><span>one</span><span>two</span><span>three</span></a><br>
+<br>
 
 <script>
 AriaUtils.verifyLabelsBySelector(".ex");
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node-expected.txt
index 2f1cf24c425b..9a90947844bb 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node-expected.txt
@@ -1,9 +1,144 @@
 Tests the #comp_text_node portions of the AccName Name Computation algorithm.
 
+text/element/text nodes, no space
+
+buttonlabel
+headinglabel
+buttonlabel
 headinglabel
 
+linklabel
+text/comment/text nodes, no space
+
+buttonlabel
+headinglabel
+buttonlabel
+headinglabel
+
+linklabel
+text/comment/text nodes, with space
+
+button label
+heading label
+button label
+heading label
+
+link label
+text node, with tab char
+
+button label
+heading label
+button label
+heading label
+
+link label
+text node, with non-breaking space
+
+button label
+heading label
+button label
+heading label
+
+link label
+text node, with extra non-breaking space
+
+button   label
+heading   label
+button   label
+heading   label
+
+link   label
+text node, with leading/trailing non-breaking space
+
+ button label 
+ heading label 
+ button label 
+ heading label 
+
+ link label 
+text node, with mixed space and non-breaking space
+
+button   label
+heading   label
+button   label
+heading   label
+
+link   label
+text nodes, with deeply nested space
+
+button label
+heading label
+button label
+heading label
+
+link label
+text nodes, with single line break
+
+button label
+heading label
+button label
 heading label
 
+link label
 
+FAIL span[role=button] with text/element/text nodes, no space assert_equals: <span role="button" tabindex="0" class="ex" data-expectedlabel="buttonlabel" data-testname="span[role=button] with text/element/text nodes, no space">button<span></span>label</span> expected "buttonlabel" but got "button label"
+FAIL div[role=heading] with text/element/text nodes, no space assert_equals: <div role="heading" class="ex" data-expectedlabel="headinglabel" data-testname="div[role=heading] with text/element/text nodes, no space">heading<span></span>label</div> expected "headinglabel" but got "heading label"
+FAIL button with text/element/text nodes, no space assert_equals: <button class="ex" data-expectedlabel="buttonlabel" data-testname="button with text/element/text nodes, no space">button<span></span>label</button> expected "buttonlabel" but got "button label"
+FAIL heading with text/element/text nodes, no space assert_equals: <h3 class="ex" data-expectedlabel="headinglabel" data-testname="heading with text/element/text nodes, no space">heading<span></span>label</h3> expected "headinglabel" but got "heading label"
+FAIL link with text/element/text nodes, no space assert_equals: <a href="#" class="ex" data-expectedlabel="linklabel" data-testname="link with text/element/text nodes, no space">link<span></span>label</a> expected "linklabel" but got "link label"
+FAIL span[role=button] with text/comment/text nodes, no space assert_equals: <span role="button" tabindex="0" class="ex" data-expectedlabel="buttonlabel" data-testname="span[role=button] with text/comment/text nodes, no space">
+  button<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</span> expected "buttonlabel" but got "button label"
+FAIL div[role=heading] with text/comment/text nodes, no space assert_equals: <div role="heading" class="ex" data-expectedlabel="headinglabel" data-testname="div[role=heading] with text/comment/text nodes, no space">
+  heading<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</div> expected "headinglabel" but got "heading label"
+FAIL button with text/comment/text nodes, no space assert_equals: <button class="ex" data-expectedlabel="buttonlabel" data-testname="button with text/comment/text nodes, no space">
+  button<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</button> expected "buttonlabel" but got "button label"
+FAIL heading with text/comment/text nodes, no space assert_equals: <h3 class="ex" data-expectedlabel="headinglabel" data-testname="heading with text/comment/text nodes, no space">
+  heading<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</h3> expected "headinglabel" but got "heading label"
+FAIL link with text/comment/text nodes, no space assert_equals: <a href="#" class="ex" data-expectedlabel="linklabel" data-testname="link with text/comment/text nodes, no space">
+  link<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</a> expected "linklabel" but got "link label"
+PASS span[role=button] with text/comment/text nodes, with space
+PASS div[role=heading] with text/comment/text nodes, with space
+PASS button with text/comment/text nodes, with space
 PASS heading with text/comment/text nodes, with space
+PASS link with text/comment/text nodes, with space
+PASS span[role=button] with text node, with tab char
+PASS div[role=heading] with text node, with tab char
+PASS button with text node, with tab char
+PASS heading with text node, with tab char
+PASS link with text node, with tab char
+PASS span[role=button] with text node, with non-breaking space
+PASS div[role=heading] with text node, with non-breaking space
+PASS button with text node, with non-breaking space
+PASS heading with text node, with non-breaking space
+PASS link with text node, with non-breaking space
+PASS span[role=button] with text node, with extra non-breaking space
+PASS div[role=heading] with text node, with extra non-breaking space
+PASS button with text node, with extra non-breaking space
+PASS heading with text node, with extra non-breaking space
+PASS link with text node, with extra non-breaking space
+PASS span[role=button] with text node, with leading/trailing non-breaking space
+PASS div[role=heading] with text node, with leading/trailing non-breaking space
+PASS button with text node, with leading/trailing non-breaking space
+PASS heading with text node, with leading/trailing non-breaking space
+PASS link with text node, with leading/trailing non-breaking space
+PASS span[role=button] with text node, with mixed space and non-breaking space
+PASS div[role=heading] with text node, with mixed space and non-breaking space
+PASS button with text node, with mixed space and non-breaking space
+PASS heading with text node, with mixed space and non-breaking space
+PASS link with text node, with mixed space and non-breaking space
+PASS span[role=button] with text node, with deeply nested space
+PASS div[role=heading] with text node, with deeply nested space
+PASS button with text node, with deeply nested space
+PASS heading with text node, with deeply nested space
+PASS link with text node, with deeply nested space
+PASS span[role=button] with text node, with single line break
+PASS div[role=heading] with text node, with single line break
+PASS button with text node, with single line break
+PASS heading with text node, with single line break
+PASS link with text node, with single line break
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node.html
index d63bdda82c0d..a31f9e02451f 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_text_node.html
@@ -13,23 +13,139 @@
 
 <p>Tests the <a href="https://w3c.github.io/accname/#comp_text_node">#comp_text_node</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
-<!-- I'm not certain whether #comp_text_node requires a lot of testing outside of the #comp_name_from_content contexts, -->
-<!-- but I did think of one example where text node versus comment node may make a difference when joining text nodes with a space vs innerText. -->
+<!--
 
-<!-- Skipped (class="ex" removed) until https://github.com/w3c/accname/issues/193 is resolved -->
-<h2 class="ex-skipped" data-expectedlabel="heading label" data-testname="heading with text/comment/text nodes, no space">
-  heading<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
-</h2>
+  Note: some overlap with the tests in:
+  - /accname/name/comp_label.html
+  - /accname/name/comp_name_from_content.html
+
+-->
+
+<h1>text/element/text nodes, no space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="buttonlabel" data-testname="span[role=button] with text/element/text nodes, no space">button<span></span>label</span>
+<div role="heading" class="ex" data-expectedlabel="headinglabel" data-testname="div[role=heading] with text/element/text nodes, no space">heading<span></span>label</div>
+<button class="ex" data-expectedlabel="buttonlabel" data-testname="button with text/element/text nodes, no space">button<span></span>label</button>
+<h3 class="ex" data-expectedlabel="headinglabel" data-testname="heading with text/element/text nodes, no space">heading<span></span>label</h3>
+<a href="#" class="ex" data-expectedlabel="linklabel" data-testname="link with text/element/text nodes, no space">link<span></span>label</a>
+<br>
 
+<h1>text/comment/text nodes, no space</h1>
+<!-- Note: This set is not currently to spec until https://github.com/w3c/accname/issues/193 is resolved. -->
+<span role="button" tabindex="0" class="ex" data-expectedlabel="buttonlabel" data-testname="span[role=button] with text/comment/text nodes, no space">
+  button<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</span>
+<div role="heading" class="ex" data-expectedlabel="headinglabel" data-testname="div[role=heading] with text/comment/text nodes, no space">
+  heading<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</div>
+<button class="ex" data-expectedlabel="buttonlabel" data-testname="button with text/comment/text nodes, no space">
+  button<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</button>
+<h3 class="ex" data-expectedlabel="headinglabel" data-testname="heading with text/comment/text nodes, no space">
+  heading<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</h3>
+<a href="#" class="ex" data-expectedlabel="linklabel" data-testname="link with text/comment/text nodes, no space">
+  link<!-- with non-text node splitting concatenated text nodes -->label<!-- [sic] no extra spaces around first comment -->
+</a>
+<br>
 
-<h2 class="ex" data-expectedlabel="heading label" data-testname="heading with text/comment/text nodes, with space">
+<h1>text/comment/text nodes, with space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button label" data-testname="span[role=button] with text/comment/text nodes, with space">
+  button
+  <!-- comment node between text nodes with leading/trailing whitespace -->
+  label
+</span>
+<div role="heading" class="ex" data-expectedlabel="heading label" data-testname="div[role=heading] with text/comment/text nodes, with space">
   heading
   <!-- comment node between text nodes with leading/trailing whitespace -->
   label
-</h2>
+</div>
+<button class="ex" data-expectedlabel="button label" data-testname="button with text/comment/text nodes, with space">
+  button
+  <!-- comment node between text nodes with leading/trailing whitespace -->
+  label
+</button>
+<h3 class="ex" data-expectedlabel="heading label" data-testname="heading with text/comment/text nodes, with space">
+  heading
+  <!-- comment node between text nodes with leading/trailing whitespace -->
+  label
+</h3>
+<a href="#" class="ex" data-expectedlabel="link label" data-testname="link with text/comment/text nodes, with space">
+  link
+  <!-- comment node between text nodes with leading/trailing whitespace -->
+  label
+</a>
+<br>
+
+<h1>text node, with tab char</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button label" data-testname="span[role=button] with text node, with tab char">button  label</span>
+<div role="heading" class="ex" data-expectedlabel="heading label" data-testname="div[role=heading] with text node, with tab char">heading label</div>
+<button class="ex" data-expectedlabel="button label" data-testname="button with text node, with tab char">button  label</button>
+<h3 class="ex" data-expectedlabel="heading label" data-testname="heading with text node, with tab char">heading label</h3>
+<a href="#" class="ex" data-expectedlabel="link label" data-testname="link with text node, with tab char">link	label</a>
+<br>
+
+<h1>text node, with non-breaking space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button&nbsp;label" data-testname="span[role=button] with text node, with non-breaking space">button&nbsp;label</span>
+<div role="heading" class="ex" data-expectedlabel="heading&nbsp;label" data-testname="div[role=heading] with text node, with non-breaking space">heading&nbsp;label</div>
+<button class="ex" data-expectedlabel="button&nbsp;label" data-testname="button with text node, with non-breaking space">button&nbsp;label</button>
+<h3 class="ex" data-expectedlabel="heading&nbsp;label" data-testname="heading with text node, with non-breaking space">heading&nbsp;label</h3>
+<a href="#" class="ex" data-expectedlabel="link&nbsp;label" data-testname="link with text node, with non-breaking space">link&nbsp;label</a>
+<br>
+
+<h1>text node, with extra non-breaking space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button&nbsp;&nbsp;&nbsp;label" data-testname="span[role=button] with text node, with extra non-breaking space">button&nbsp;&nbsp;&nbsp;label</span>
+<div role="heading" class="ex" data-expectedlabel="heading&nbsp;&nbsp;&nbsp;label" data-testname="div[role=heading] with text node, with extra non-breaking space">heading&nbsp;&nbsp;&nbsp;label</div>
+<button class="ex" data-expectedlabel="button&nbsp;&nbsp;&nbsp;label" data-testname="button with text node, with extra non-breaking space">button&nbsp;&nbsp;&nbsp;label</button>
+<h3 class="ex" data-expectedlabel="heading&nbsp;&nbsp;&nbsp;label" data-testname="heading with text node, with extra non-breaking space">heading&nbsp;&nbsp;&nbsp;label</h3>
+<a href="#" class="ex" data-expectedlabel="link&nbsp;&nbsp;&nbsp;label" data-testname="link with text node, with extra non-breaking space">link&nbsp;&nbsp;&nbsp;label</a>
+<br>
+
+<h1>text node, with leading/trailing non-breaking space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button&nbsp;label" data-testname="span[role=button] with text node, with leading/trailing non-breaking space">&nbsp;button&nbsp;label&nbsp;</span>
+<div role="heading" class="ex" data-expectedlabel="heading&nbsp;label" data-testname="div[role=heading] with text node, with leading/trailing non-breaking space">&nbsp;heading&nbsp;label&nbsp;</div>
+<button class="ex" data-expectedlabel="button&nbsp;label" data-testname="button with text node, with leading/trailing non-breaking space">&nbsp;button&nbsp;label&nbsp;</button>
+<h3 class="ex" data-expectedlabel="heading&nbsp;label" data-testname="heading with text node, with leading/trailing non-breaking space">&nbsp;heading&nbsp;label&nbsp;</h3>
+<a href="#" class="ex" data-expectedlabel="link&nbsp;label" data-testname="link with text node, with leading/trailing non-breaking space">&nbsp;link&nbsp;label&nbsp;</a>
+<br>
+
+<h1>text node, with mixed space and non-breaking space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button &nbsp; label" data-testname="span[role=button] with text node, with mixed space and non-breaking space">button   &nbsp;   label</span>
+<div role="heading" class="ex" data-expectedlabel="heading &nbsp; label" data-testname="div[role=heading] with text node, with mixed space and non-breaking space">heading   &nbsp;   label</div>
+<button class="ex" data-expectedlabel="button &nbsp; label" data-testname="button with text node, with mixed space and non-breaking space">button   &nbsp;   label</button>
+<h3 class="ex" data-expectedlabel="heading &nbsp; label" data-testname="heading with text node, with mixed space and non-breaking space">heading   &nbsp;   label</h3>
+<a href="#" class="ex" data-expectedlabel="link &nbsp; label" data-testname="link with text node, with mixed space and non-breaking space">link   &nbsp;   label</a>
+<br>
 
+<h1>text nodes, with deeply nested space</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button label" data-testname="span[role=button] with text node, with deeply nested space">
+button<span><span><span><span><span><span><span> </span></span></span></span></span></span></span>label
+</span>
+<div role="heading" class="ex" data-expectedlabel="heading label" data-testname="div[role=heading] with text node, with deeply nested space">
+heading<span><span><span><span><span><span><span> </span></span></span></span></span></span></span>label
+</div>
+<button class="ex" data-expectedlabel="button label" data-testname="button with text node, with deeply nested space">
+button<span><span><span><span><span><span><span> </span></span></span></span></span></span></span>label
+</button>
+<h3 class="ex" data-expectedlabel="heading label" data-testname="heading with text node, with deeply nested space">
+heading<span><span><span><span><span><span><span> </span></span></span></span></span></span></span>label
+</h3>
+<a href="#" class="ex" data-expectedlabel="link label" data-testname="link with text node, with deeply nested space">
+link<span><span><span><span><span><span><span> </span></span></span></span></span></span></span>label
+</a>
+<br>
 
-<!-- Todo: test all remaining cases of https://w3c.github.io/accname/#comp_text_node -->
+<h1>text nodes, with single line break</h1>
+<span role="button" tabindex="0" class="ex" data-expectedlabel="button label" data-testname="span[role=button] with text node, with single line break">button
+label</span>
+<div role="heading" class="ex" data-expectedlabel="heading label" data-testname="div[role=heading] with text node, with single line break">heading
+label</div>
+<button class="ex" data-expectedlabel="button label" data-testname="button with text node, with single line break">button
+label</button>
+<h3 class="ex" data-expectedlabel="heading label" data-testname="heading with text node, with single line break">heading
+label</h3>
+<a href="#" class="ex" data-expectedlabel="link label" data-testname="link with text node, with single line break">link
+label</a>
+<br>
 
 <script>
 AriaUtils.verifyLabelsBySelector(".ex");
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip-expected.txt b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip-expected.txt
index d96ba1c50a26..d1af8e8ac129 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip-expected.txt
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip-expected.txt
@@ -1,6 +1,28 @@
 Tests the #comp_tooltip portions of the AccName Name Computation algorithm.
 
+ content
+content
+           button WPT CTRL + OPT
+summary
 
 
-PASS link label from tooltip
+PASS link with img with tooltip label
+FAIL link with text with tooltip label assert_equals: <a href="#" title="label" data-expectedlabel="label" data-testname="link with text with tooltip label" class="ex">content</a> expected "label" but got "content"
+PASS div with text with tooltip label
+PASS img with tooltip label without alt
+PASS img with tooltip label with empty alt
+PASS img with tooltip label with alt
+PASS img with tooltip label without title
+PASS textarea with placeholder and tooltip label
+PASS text input with placeholder and tooltip label
+PASS email input with placeholder and tooltip label
+PASS password input with placeholder and tooltip label
+PASS checkbox input with tooltip label
+PASS radio input with tooltip label
+FAIL button with tooltip label assert_equals: <button title="label" data-expectedlabel="label" data-testname="button with tooltip label" class="ex">button</button> expected "label" but got "button"
+PASS abbr with tooltip label
+PASS kbd with tooltip label
+PASS select with tooltip label
+PASS summary with tooltip label
+PASS iframe with tooltip label
 
diff --git a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip.html b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip.html
index 34718bd025f0..bcb17d3418ae 100644
--- a/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip.html
+++ b/LayoutTests/imported/w3c/web-platform-tests/accname/name/comp_tooltip.html
@@ -11,11 +11,39 @@
 </head>
 <body>
 
-  <p>Tests the <a href="https://w3c.github.io/accname/#comp_tooltip">#comp_tooltip</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
+<p>Tests the <a href="https://w3c.github.io/accname/#comp_tooltip">#comp_tooltip</a> portions of the AccName <em>Name Computation</em> algorithm.</p>
 
-<a href="#" title="label" data-expectedlabel="label" data-testname="link label from tooltip" class="ex"><img src="#" alt=""></a>
+<a href="#" title="label" data-expectedlabel="label" data-testname="link with img with tooltip label" class="ex"><img src="#" alt=""></a>
+<a href="#" title="label" data-expectedlabel="label" data-testname="link with text with tooltip label" class="ex">content</a>
+<div title="label" role="group" data-expectedlabel="label" data-testname="div with text with tooltip label" class="ex">content</div>
+<img src="foo.jpg" title="label" data-expectedlabel="label" data-testname="img with tooltip label without alt" class="ex">
+<img src="foo.jpg" title="label" data-expectedlabel="label" alt="" data-testname="img with tooltip label with empty alt" class="ex">
+<img src="foo.jpg" title="label" data-expectedlabel="broken" alt="broken" data-testname="img with tooltip label with alt" class="ex">
+<img src="foo.jpg" data-expectedlabel="broken" alt="broken" data-testname="img with tooltip label without title" class="ex">
 
-<!-- Todo: test all remaining cases of https://w3c.github.io/accname/#comp_tooltip -->
+<textarea title="enter text" data-expectedlabel="enter text" placeholder="textarea" data-testname="textarea with placeholder and tooltip label" class="ex"></textarea>
+<input type="text" title="label" data-expectedlabel="label" placeholder="text" data-testname="text input with placeholder and tooltip label" class="ex">
+<input type="email" title="label" data-expectedlabel="label" placeholder="email" data-testname="email input with placeholder and tooltip label" class="ex">
+<input type="password" title="label" data-expectedlabel="label" placeholder="password" data-testname="password input with placeholder and tooltip label" class="ex">
+<input type="checkbox" title="label" data-expectedlabel="label" data-testname="checkbox input with tooltip label" class="ex">
+<input type="radio" title="label" data-expectedlabel="label" data-testname="radio input with tooltip label" class="ex">
+<button title="label" data-expectedlabel="label" data-testname="button with tooltip label" class="ex">button</button>
+<abbr title="Web Platform Tests" data-expectedlabel="Web Platform Tests" data-testname="abbr with tooltip label" class="ex">WPT</abbr>
+<kbd title="Control + Option" data-expectedlabel="Control + Option" data-testname="kbd with tooltip label" class="ex">CTRL + OPT</kbd>
+
+<select title="label" data-expectedlabel="label" data-testname="select with tooltip label" class="ex">
+  <option value="" disabled selected>select options</option>
+  <option value="1">option 1</option>
+  <option value="2">option 2</option>
+  <option value="3">option 3</option>
+</select>
+
+<details>
+  <summary title="label" data-expectedlabel="label" data-testname="summary with tooltip label" class="ex">summary</summary>
+  details
+</details>
+
+<iframe title="label" data-expectedlabel="label" data-testname="iframe with tooltip label" width="20px" height="20px" class="ex"></iframe>
 
 <script>
 AriaUtils.verifyLabelsBySelector(".ex");
diff --git a/LayoutTests/platform/mac/TestExpectations b/LayoutTests/platform/mac/TestExpectations
index 464f7800c415..084f7a5a2189 100644
--- a/LayoutTests/platform/mac/TestExpectations
+++ b/LayoutTests/platform/mac/TestExpectations
@@ -2433,9 +2433,6 @@ webkit.org/b/259190 http/tests/images/heic-as-heif.html [ Pass ImageOnlyFailure
 [ Monterey ] imported/w3c/web-platform-tests/mathml/relations/css-styling/width-height-001.html [ Pass Failure ]
 [ Monterey ] imported/w3c/web-platform-tests/mathml/relations/html5-tree/dynamic-childlist-002.html [ Pass Failure ]
 
-# Sonoma has one extra whitespace for some reason.
-[ Sonoma+ ] imported/w3c/web-platform-tests/accname/name/comp_host_language_label.html [ Failure ]
-
 webkit.org/b/260224 [ Ventura+ ] compositing/geometry/clipped-out-perspective.html [ ImageOnlyFailure ]
 webkit.org/b/260224 [ Ventura+ ] compositing/overlap-blending/opacity-and-infinity.html [ ImageOnlyFailure ]
 webkit.org/b/260224 [ Ventura+ ] imported/w3c/web-platform-tests/css/css-transforms/perspective-split-by-zero-w.html [ ImageOnlyFailure ]