diff --git a/source b/source
index b7d731bcacb..7910d1777e1 100644
--- a/source
+++ b/source
@@ -95068,7 +95068,7 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
<li><p><span>Inform the navigation API about child navigable destruction</span> given
<var>navigable</var>.</p></li>
- <li><p><span data-x="destroy a document">Destroy</span> <var>navigable</var>'s <span
+ <li><p><span>Destroy a document and its descendants</span> given <var>navigable</var>'s <span
data-x="nav-document">active document</span>.</p></li>
<li><p>Let <var>parentDocState</var> be <var>container</var>'s <span>node navigable</span>'s
@@ -95110,8 +95110,8 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
<li><p>Let <var>document</var> be <var>historyEntry</var>'s <span
data-x="she-document">document</span>.</p></li>
- <li><p>If <var>document</var> is not null, then <span data-x="destroy a
- document">destroy</span> <var>document</var>.</p></li>
+ <li><p>If <var>document</var> is not null, then <span>destroy a document and its
+ descendants</span> given <var>document</var>.</p></li>
</ol>
</li>
@@ -95139,12 +95139,18 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
<li><p>If the result of <span>checking if unloading is canceled</span> for <var>toUnload</var> is
true, then return.</p></li>
- <li><p><span data-x="unload a document">Unload</span> the <span data-x="nav-document">active
- documents</span> of each of <var>toUnload</var>. <span class="XXX" data-x="">In what
- order?</span></p></li>
+ <li>
+ <p><span data-x="tn-append-session-history-traversal-steps">Append the following session
+ history traversal steps</span> to <var>traversable</var>:</p>
- <li><p><span data-x="destroy a top-level traversable">Destroy</span>
- <var>traversable</var>.</p></li>
+ <ol>
+ <li><p>Let <var>afterAllUnloads</var> be an algorithm step which <span data-x="destroy a
+ top-level traversable">destroys</span> <var>traversable</var>.</p></li>
+
+ <li><p><span>Unload a document and its descendants</span> given <var>traversable</var>'s <span
+ data-x="nav-document">active document</span>, null, and <var>afterAllUnloads</var>.</p></li>
+ </ol>
+ </li>
</ol>
@@ -96363,7 +96369,7 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
name</dfn> string, initially the empty string.</p></li>
</ul>
- <p>User agents may <span data-x="destroy a Document">destroy</span> the <span
+ <p>User agents may <span>destroy a document and its descendants</span> given the <span
data-x="document-state-document">documents</span> of <span data-x="document state">document
states</span> with non-null <span data-x="document-state-document">documents</span>, as long as
the <code>Document</code> is not <span>fully active</span>.</p>
@@ -97446,7 +97452,7 @@ location.href = '#foo';</code></pre>
<li><p><span>Queue a global task</span> on the <span>navigation and traversal task
source</span> given <var>navigable</var>'s <span data-x="nav-window">active window</span> to
- <span data-x="abort a document">abort</span> <var>navigable</var>'s <span
+ <span>abort a document and its descendants</span> given <var>navigable</var>'s <span
data-x="nav-document">active document</span>.</p></li>
<li id="navigation-create-document-state">
@@ -100511,36 +100517,24 @@ location.href = '#foo';</code></pre>
<var>targetStep</var>.</p></li>
<li>
- <p><span>Queue a global task</span> on the <span>navigation and traversal task source</span>
- given <var>navigable</var>'s <span data-x="nav-window">active window</span> to run the
- steps:</p>
+ <p>If <var>changingNavigableContinuation</var>'s <span
+ data-x="changing-nav-continuation-update-only">update-only</span> is false, and
+ <var>targetEntry</var>'s <span data-x="she-document">document</span> does not equal
+ <var>displayedDocument</var>, then <span>unload a document and its descendants</span> given
+ <var>displayedDocument</var>, <var>targetEntry</var>'s <span
+ data-x="she-document">document</span>, and <var>afterPotentialUnloads</var>.</p>
- <ol>
- <li>
- <p>If <var>changingNavigableContinuation</var>'s <span
- data-x="changing-nav-continuation-update-only">update-only</span> is false, then:</p>
+ <p>Otherwise, <span>queue a global task</span> on the <span>navigation and traversal task
+ source</span> given <var>navigable</var>'s <span data-x="nav-window">active window</span> to
+ perform <var>afterPotentialUnloads</var>.</p>
- <ol>
- <li>
- <p>If <var>targetEntry</var>'s <span data-x="she-document">document</span> does not equal
- <var>displayedDocument</var>, then:</p>
+ <p>In both cases, let <var>afterPotentialUnloads</var> be the following steps:</p>
- <ol>
- <li><p><span data-x="unload a document">Unload</span> <var>displayedDocument</var> given
- <var>targetEntry</var>'s <span data-x="she-document">document</span>.</p></li>
-
- <li><p>For each <var>childNavigable</var> of <var>displayedDocument</var>'s
- <span>descendant navigables</span>, <span>queue a global task</span> on the
- <span>navigation and traversal task source</span> given <var>childNavigable</var>'s
- <span data-x="nav-window">active window</span> to <span data-x="unload a
- document">unload</span> <var>childNavigable</var>'s <span data-x="nav-document">active
- document</span>.</p></li>
- </ol>
-
- <li><p><span>Activate history entry</span> <var>targetEntry</var> for
- <var>navigable</var>.</p></li>
- </ol>
- </li>
+ <ol>
+ <li><p>If <var>changingNavigableContinuation</var>'s <span
+ data-x="changing-nav-continuation-update-only">update-only</span> is false, then
+ <span>activate history entry</span> <var>targetEntry</var> for
+ <var>navigable</var>.</p></li>
<li><p>Let <var>updateDocument</var> be an algorithm step which performs <span>update
document for history step application</span> given <var>targetEntry</var>'s <span
@@ -102188,7 +102182,8 @@ new PaymentRequest(…); // Allowed to use
<ol>
<li><p><span>Assert</span>: this is running as part of a <span data-x="concept-task">task</span>
- queued on <var>oldDocument</var>'s <span>event loop</span>.</p></li>
+ queued on <var>oldDocument</var>'s <span>relevant agent</span>'s <span
+ data-x="concept-agent-event-loop">event loop</span>.</p></li>
<li><p>Let <var>unloadTimingInfo</var> be a new <span>document unload timing
info</span>.</p></li>
@@ -102295,6 +102290,54 @@ new PaymentRequest(…); // Allowed to use
<var>unloadTimingInfo</var>.</p></li>
</ol>
+ <p>To <dfn>unload a document and its descendants</dfn>, given a <code>Document</code>
+ <var>document</var>, an optional <code>Document</code>-or-null <var>newDocument</var> (default
+ null), and an optional set of steps <var>afterAllUnloads</var>:</p>
+
+ <ol>
+ <li><p><span>Assert</span>: this is running within <var>document</var>'s <span>node
+ navigable</span>'s <span data-x="nav-traversable">traversable navigable</span>'s <span
+ data-x="tn-session-history-traversal-queue">session history traversal queue</span>.</p></li>
+
+ <li><p>Let <var>childNavigables</var> be <var>document</var>'s <span data-x="child
+ navigable">child navigables</span>.</p></li>
+
+ <li><p>Let <var>numberUnloaded</var> be 0.</p></li>
+
+ <li>
+ <p><span data-x="list iterate">For each</span> <var>childNavigable</var> of
+ <var>childNavigable</var>'s <span class="XXX" data-x="">in what order?</span>, <span>queue a
+ global task</span> on the <span>navigation and traversal task source</span> given
+ <var>childNavigable</var>'s <span data-x="nav-window">active window</span> to perform the
+ following steps:</p>
+
+ <ol>
+ <li><p>Let <var>incrementUnloaded</var> be an algorithm step which increments
+ <var>numberUnloaded</var>.</p></li>
+
+ <li><p><span>Unload a document and its descendants</span> given <var>childNavigable</var>'s
+ <span data-x="nav-document">active document</span>, null, and
+ <var>incrementUnloaded</var>.</p></li>
+ </ol>
+ </li>
+
+ <li><p>Wait until <var>numberUnloaded</var> equals <var>childNavigable</var>'s <span
+ data-x="list size">size</span>.</p></li>
+
+ <li>
+ <p><span>Queue a global task</span> on the <span>navigation and traversal task source</span>
+ given <var>document</var>'s <span>relevant global object</span> to perform the following
+ steps:</p>
+
+ <ol>
+ <li><p><span data-x="unload a document">Unload</span> <var>document</var>, passing along
+ <var>newDocument</var> if it is not null.</p></li>
+
+ <li><p>If <var>afterAllUnloads</var> was given, then run it.</p></li>
+ </ol>
+ </li>
+ </ol>
+
<p>This specification defines the following <dfn export>unloading document cleanup steps</dfn>.
Other specifications can define more. Given a <code>Document</code> <var>document</var>:</p>
@@ -102354,9 +102397,11 @@ new PaymentRequest(…); // Allowed to use
<code>Document</code> <var>document</var>:</p>
<ol>
- <li><p><span data-x="destroy a document">Destroy</span> the <span
- data-x="nav-document">active documents</span> of each of <var>document</var>'s <span>descendant
- navigables</span>. <span class="XXX" data-x="">In what order?</span></p></li>
+ <li><p><span>Assert</span>: this is running as part of a <span data-x="concept-task">task</span>
+ queued on <var>document</var>'s <span>relevant agent</span>'s <span
+ data-x="concept-agent-event-loop">event loop</span>.</p></li>
+
+ <li><p><span data-x="abort a document">Abort</span> <var>document</var>.</p></li>
<li><p>Set <var>document</var>'s <i data-x="concept-document-salvageable">salvageable</i> state
to false.</p></li>
@@ -102364,8 +102409,6 @@ new PaymentRequest(…); // Allowed to use
<li><p>Run any <span>unloading document cleanup steps</span> for <var>document</var> that
are defined by this specification and <span>other applicable specifications</span>.</p></li>
- <li><p><span data-x="abort a document">Abort</span> <var>document</var>.</p></li>
-
<li><p>Remove any <span data-x="concept-task">tasks</span> whose <span
data-x="concept-task-document">document</span> is <var>document</var> from any <span>task
queue</span> (without running those tasks).</p></li>
@@ -102392,22 +102435,61 @@ new PaymentRequest(…); // Allowed to use
accessible to script, in the case where we are <span data-x="destroy a child
navigable">destroying a child navigable</span>.</p>
+ <p>To <dfn>destroy a document and its descendants</dfn> given a <code>Document</code>
+ <var>document</var> and an optional set of steps <var>afterAllDestruction</var>, perform the
+ following steps <span>in parallel</span>:</p>
+
+ <ol>
+ <li><p>Let <var>childNavigables</var> be <var>document</var>'s <span data-x="child
+ navigable">child navigables</span>.</p></li>
+
+ <li><p>Let <var>numberDestroyed</var> be 0.</p></li>
+
+ <li>
+ <p><span data-x="list iterate">For each</span> <var>childNavigable</var> of
+ <var>childNavigable</var>'s <span class="XXX" data-x="">in what order?</span>, <span>queue a
+ global task</span> on the <span>navigation and traversal task source</span> given
+ <var>childNavigable</var>'s <span data-x="nav-window">active window</span> to perform the
+ following steps:</p>
+
+ <ol>
+ <li><p>Let <var>incrementDestroyed</var> be an algorithm step which increments
+ <var>numberDestroyed</var>.</p></li>
+
+ <li><p><span>Destroy a document and its descendants</span> given <var>childNavigable</var>'s
+ <span data-x="nav-document">active document</span> and <var>incrementDestroyed</var>.</p></li>
+ </ol>
+ </li>
+
+ <li><p>Wait until <var>numberDestroyed</var> equals <var>childNavigable</var>'s <span
+ data-x="list size">size</span>.</p></li>
+
+ <li>
+ <p><span>Queue a global task</span> on the <span>navigation and traversal task source</span>
+ given <var>document</var>'s <span>relevant global object</span> to perform the following
+ steps:</p>
+
+ <ol>
+ <li><p><span data-x="destroy a document">Destroy</span> <var>document</var>.</p></li>
+
+ <li><p>If <var>afterAllDestruction</var> was given, then run it.</p></li>
+ </ol>
+ </li>
+ </ol>
+
<h4>Aborting a document load</h4>
<p>To <dfn data-x="abort a document">abort</dfn> a <code>Document</code> <var>document</var>:</p>
<ol>
- <li><p><span data-x="abort a document">Abort</span> the <span data-x="nav-document">active
- documents</span> of each of <var>document</var>'s <span>descendant navigables</span>. <span
- class="XXX" data-x="">In what order?</span> If this results in any of those <code>Document</code>
- objects having their <i data-x="concept-document-salvageable">salvageable</i> state set to false,
- then set <var>document</var>'s <i data-x="concept-document-salvageable">salvageable</i> state to
- false also.</p></li>
+ <li><p><span>Assert</span>: this is running as part of a <span data-x="concept-task">task</span>
+ queued on <var>document</var>'s <span>relevant agent</span>'s <span
+ data-x="concept-agent-event-loop">event loop</span>.</p></li>
<li><p>Cancel any instances of the <span data-x="concept-fetch">fetch</span> algorithm in the
- context of <var>document</var>, discarding any <span data-x="concept-task">tasks</span>
- <span data-x="queue a task">queued</span> for them, and discarding any further data received from
- the network for them. If this resulted in any instances of the <span
+ context of <var>document</var>, discarding any <span data-x="concept-task">tasks</span> <span
+ data-x="queue a task">queued</span> for them, and discarding any further data received from the
+ network for them. If this resulted in any instances of the <span
data-x="concept-fetch">fetch</span> algorithm being canceled or any <span data-x="queue a
task">queued</span> <span data-x="concept-task">tasks</span> or any network data getting
discarded, then set <var>document</var>'s <i
@@ -102440,10 +102522,42 @@ new PaymentRequest(…); // Allowed to use
<li><p><span data-x="abort a parser">Abort that parser</span>.</p></li>
- <li><p>Set <var>document</var>'s <i data-x="concept-document-salvageable">salvageable</i> state
- to false.</p></li>
+ <li><p>Set <var>document</var>'s <i data-x="concept-document-salvageable">salvageable</i> to
+ false.</p></li>
+ </ol>
+ </li>
+ </ol>
+
+ <p>To <dfn>abort a document and its descendants</dfn> given a <code>Document</code>
+ <var>document</var>:</p>
+
+ <ol>
+ <li><p><span>Assert</span>: this is running as part of a <span data-x="concept-task">task</span>
+ queued on <var>document</var>'s <span>relevant agent</span>'s <span
+ data-x="concept-agent-event-loop">event loop</span>.</p></li>
+
+ <li><p>Let <var>descendantNavigables</var> be <var>document</var>'s <span>descendant
+ navigables</span>.</p></li>
+
+ <li>
+ <p><span data-x="list iterate">For each</span> <var>descendantNavigable</var> of
+ <var>descendantNavigables</var> <span class="XXX" data-x="">in what order?</span>, <span>queue
+ a global task</span> on the <span>navigation and traversal task source</span> given
+ <var>descendantNavigable</var>'s <span data-x="nav-window">active window</span> to perform the
+ following steps:</p>
+
+ <ol>
+ <li><p><span data-x="abort a document">Abort</span> <var>descendantNavigable</var>'s <span
+ data-x="nav-document">active document</span>.</p></li>
+
+ <li><p>If <var>descendantNavigable</var>'s <span data-x="nav-document">active
+ document</span>'s <i data-x="concept-document-salvageable">salvageable</i> is false, then set
+ <var>document</var>'s <i data-x="concept-document-salvageable">salvageable</i> to
+ false.</p></li>
</ol>
</li>
+
+ <li><p><span data-x="abort a document">Abort</span> <var>document</var>.</p></li>
</ol>
<p id="stop-document-loading">To <dfn data-x="nav-stop">stop loading</dfn> a
@@ -102463,7 +102577,7 @@ new PaymentRequest(…); // Allowed to use
navigation</span> will cause further work to be abandoned.</p>
</li>
- <li><p><span data-x="abort a document">Abort</span> <var>document</var>.</p></li>
+ <li><p><span>Abort a document and its descendants</span> given <var>document</var>.</p></li>
</ol>
<p class="XXX">Through their <a href="#nav-traversal-ui">user interface</a>, user agents also