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Turn quota example into a tree
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‎fetch.bs

Lines changed: 76 additions & 131 deletions
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@@ -2777,7 +2777,7 @@ not <a for=Document>fully active</a>. It has the following <a for=struct>items</
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false, <a for="fetch controller">terminate</a> <var>record</var>'s
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<a for="fetch record">controller</a>.
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<li><p><a>Process or propagate deferred fetches</a> for <var>fetchGroup</var>.
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<li><p><a>Process deferred fetches</a> for <var>fetchGroup</var>.
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</ol>
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@@ -6764,6 +6764,8 @@ sources, specifically task sources that can result in running scripts such as th
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takes no arguments:
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<ol>
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<li><p>Assert: <var>request</var>'s <a for=request>client</a> is a {{Document}}.
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<li><p><a>Populate request from client</a> given <var>request</var>.
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<li><p>Set <var>request</var>'s <a for=request>service-workers mode</a> to "<code>none</code>".
@@ -6773,9 +6775,22 @@ takes no arguments:
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<li><p>Let <var>deferredRecord</var> be a new <a>deferred fetch record</a> whose
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<a for="deferred fetch record">request</a> is <var>request</var>.
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6776-
<li><p><a for=list>Append</a> <var>deferredRecord</var> to <var>request</var>'s
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<a for=request>client</a>'s <a for=fetch>fetch group</a>'s
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<a for="fetch group">deferred fetch records</a>.
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<li><p>Let <var>topMostDirectSameOriginAncestor</var> be var>request</var>'s
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<a for=request>client</a>.
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<li><p>While <var>topMostDirectSameOriginAncestor</var>'s <a>node navigable</a>'s
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<a>container document</a> is a {{Document}} whose <a for=Document>origin</a> is <a>same origin</a>
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with <var>request</var>'s <a for=request>client</a>'s <a for=Document>origin</a>, set
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<var>topMostDirectSameOriginAncestor</var> to <var>topMostDirectSameOriginAncestor</var>'s
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<a>node navigable</a>'s <a>container document</a>.
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<li>
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<p><a for=list>Append</a> <var>deferredRecord</var> to
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<var>topMostDirectSameOriginAncestor</var>'s <a>active document</a>'s
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<a for=fetch>fetch group</a>'s <a for="fetch group">deferred fetch records</a>.
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<p class=note>This prevents a case where eagerly creating and destroying nested documents would
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circumvent the keepalive quota.
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<li>
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<p>If <var>activateAfter</var> is non-null, then run the following steps <a>in parallel</a>:</p>
@@ -6825,26 +6840,11 @@ takes no arguments:
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</div>
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<div algorithm>
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<p>To <dfn>process or propagate deferred fetches</dfn> given a <a>fetch group</a>
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<p>To <dfn>process deferred fetches</dfn> given a <a>fetch group</a>
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<var>fetchGroup</var>, <a for=list>for each</a> <a for="fetch group">deferred fetch record</a>
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<var>deferredRecord</var> of <var>fetchGroup</var>'s
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<a for="fetch group">deferred fetch records</a>:
6832-
6833-
<ol>
6834-
<li><p>Let <var>document</var> be <var>deferredRecord</var>'s
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<a for="deferred fetch record">request</a>'s <a for=request>client</a>.
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6837-
<li><p>Let <var>parent</var> be <var>document</var>'s <a>node navigable</a>'s
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<a>container document</a>.
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<li><p>If <var>parent</var> is a <a>fully active</a> {{Document}} whose
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<a for=Document>origin</a> is <a>same origin</a> with <var>document</var>'s
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<a for=Document>origin</a>, then set <var>deferredRecord</var>'s
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<a for="deferred fetch record">request</a>'s <a for=request>client</a> to <var>parent</var> and
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<a for=list>append</a> <var>deferredRecord</var> to <var>parent</var>'s
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<a for=fetch>fetch group</a>'s <a for="fetch group">deferred fetch records</a>.
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6847-
<li><p>Otherwise, .
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<a for="fetch group">deferred fetch records</a> <a>process a deferred fetch</a>
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<var>deferredRecord</var>.
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</ol>
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</div>
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@@ -6893,13 +6893,14 @@ opportunistically, before they have data to send.
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<div class=example id=deferred-fetch-quota-examples>
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<p>Any of the following calls to <a method><code>fetchLater()</code></a> would throw due to
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the request itself exceeding the 64 kibibytes quota allocated to a reporting origin. Note that the
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size of the request includes the <a for=request>URL</a> itself, the <a for=request>body</a>, and the
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<a for=request>header list</a>.
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size of the request includes the <a for=request>URL</a> itself, the <a for=request>body</a>, the
6897+
<a for=request>header list</a>, and the <a for=request>referrer</a>.
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<pre><code class=lang-javascript>
6899-
fetchLater(a_64_kb_url);
6899+
fetchLater(a_72_kb_url);
69006900
fetchLater("https://origin.example.com", {headers: headers_exceeding_64kb});
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fetchLater(a_32_kb_url, {headers: headers_exceeding_32kb});
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fetchLater("https://origin.example.com", {method: "POST", body: body_exceeding_64_kb});
6903+
fetchLater(a_62_kb_url /* with a 3kb referrer */);
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</code></pre>
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<p>In the following sequence, the first two requests would succeed, but the third one would throw.
@@ -6919,125 +6920,69 @@ calls would succeed and the last one would throw.
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// In main page
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fetchLater("https://a.example.com", {method: "POST", body: a_64kb_body});
69216922

6922-
// In same-origin iframe
6923+
// In same-origin nested document
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fetchLater("https://b.example.com", {method: "POST", body: a_64kb_body});
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6925-
// In cross-origin iframe at https://frame.example.com
6926+
// In cross-origin nested document at https://frame.example.com
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fetchLater("https://a.example.com", {body: a_5kb_body});
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fetchLater("https://a.example.com", {body: a_12kb_body});
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</code></pre>
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<p>To make the previous example not throw, the top-level {{Document}} can delegate some of its quota
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to <code>https://frame.example.com</code>, for example by serving the following header:
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<pre><code class=lang-http>Permissions-Policy: deferred-fetch=(self "https://frame.example.com")</code></pre>
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6934-
<p>The following tables illustrates how quota is distributed to different iframes, each table
6935-
representing a different <a for=/>top-level traversable</a> ("tab").
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6937-
<p>For a tree with its top-level <code>Permissions-Policy</code> header set to
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<code class=lang-http>deferred-fetch=(self "https://ok.example.com")</code>:
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6940-
<table>
6941-
<tr>
6942-
<th>Window name
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<th>Parent
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<th>Initial origin
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<th>Current origin
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<th>Quota
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<tr>
6948-
<td><code>top</code>
6949-
<td><code>null</code>
6950-
<td><code>https://me.example.com</code>
6951-
<td><code>https://me.example.com</code>
6952-
<td>384 kibibytes (512 - 64 - 64). <code>d</code> and frame <code>g</code> were granted
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64 kibibytes each, even though for <code>g</code> this quota ended up being unavailable.
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<tr>
6955-
<td><code>a</code>
6956-
<td><code>top</code>
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<td><code>https://me.example.com</code>
6958-
<td><code>https://me.example.com</code>
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<td>Shared with <code>top</code>'s quota.
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<tr>
6961-
<td><code>b</code>
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<td><code>a</code>
6963-
<td><code>https://x.example.com</code>
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<td><code>https://x.example.com</code>
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<td>8 kibibytes, due to the default "{{PermissionsPolicy/deferred-fetch-minimal}}" policy.
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<tr>
6967-
<td><code>c</code>
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<td><code>top</code>
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<td><code>https://x.example.com</code>
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<td><code>https://x.example.com</code>
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<td>8 kibibytes, due to the default "{{PermissionsPolicy/deferred-fetch-minimal}}" policy.
6972-
<tr>
6973-
<td><code>d</code>
6974-
<td><code>top</code>
6975-
<td><code>https://ok.example.com</code>
6976-
<td><code>https://ok.example.com</code>
6977-
<td>64 kibibytes, due to the "{{PermissionsPolicy/deferred-fetch}}" policy.
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<tr>
6979-
<td><code>e</code>
6980-
<td><code>d</code>
6981-
<td><code>https://x.example.com</code>
6982-
<td><code>https://x.example.com</code>
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<td>0, as its parent doesn't share the quota with the top-level document.
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<tr>
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<td><code>f</code>
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<td><code>d</code>
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<td><code>https://me.example.com</code>
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<td><code>https://me.example.com</code>
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<td>Shared with <code>top</code>'s quota.
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<tr>
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<td><code>g</code>
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<td><code>top</code>
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<td><code>https://ok.example.com</code>
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<td><code>https://x.example.com</code>
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<td>0, as the reserved quota when navigating doesn't match the current {{PermissionsPolicy}}.
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<tr>
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<td><code>h</code>
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<td><code>top</code>
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<td><code>https://ok.example.com</code>
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<td><code>https://me.example.com</code>
7001-
<td>Shared with <code>top</code>'s quota.
7002-
</table>
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<p>Each nested document reserves its own quota, and all the same-origin documents in the tree share
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quota with each other. So the following would work, because each frame reserve 8 kibibytes and they
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share the accumulated 16 kibibytes:
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<pre><code class=lang-javascript>
6940+
// In cross-origin nested document at https://frame.example.com/frame-1
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fetchLater("https://a.example.com", {body: a_6kb_body});
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7004-
<p>For a tree with its top-level <code>Permissions-Policy</code> header set to
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<code class=lang-http>deferred-fetch-minimal=(); deferred-fetch=(self https://ok.example.com)</code>:
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// In cross-origin nested document at https://frame.example.com/frame-2
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fetchLater("https://a.example.com", {body: a_6kb_body});
6945+
</code></pre>
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7007-
<table>
7008-
<tr>
7009-
<th>Window name
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<th>Parent
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<th>Initial origin
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<th>Current origin
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<th>Quota
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<tr>
7015-
<td><code>top</code>
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<td><code>null</code>
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<td><code>https://me.example.com</code>
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<td><code>https://me.example.com</code>
7019-
<td>576kb (640kb - 64kb). <code>c</code> was granted 64kb. Since "{{PermissionsPolicy/deferred-fetch-minimal}}"
7020-
was explicitly disabled, the initial top-level quota is 640kb instead of 512kb.
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<tr>
7022-
<td><code>a</code>
7023-
<td><code>top</code>
7024-
<td><code>https://me.example.com</code>
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<td><code>https://me.example.com</code>
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<td>Shared with <code>top</code>'s quota.
7027-
<tr>
7028-
<td><code>b</code>
7029-
<td><code>a</code>
7030-
<td><code>https://x.example.com</code>
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<td><code>https://x.example.com</code>
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<td>0, due to the "{{PermissionsPolicy/deferred-fetch-minimal}}" being explicitly disabled.
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<tr>
7034-
<td><code>c</code>
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<td><code>top</code>
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<td><code>https://ok.example.com</code>
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<td><code>https://ok.example.com</code>
7038-
<td>64kb, due to the "{{PermissionsPolicy/deferred-fetch}}" policy.
7039-
</table>
6947+
<p>The following chart illustrates how quota is distributed to different nested documents in a tree:
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6949+
<pre><code>
6950+
+ https://me.example.com with Permissions-policy: deferred-fetch=(self "https://ok.example.com")
6951+
|
6952+
+ ---- + https://me.example.com
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| | Shares quota with the <a for=/>top-level traversable</a>, as they're same origin.
6954+
| |
6955+
| + ---- + https://x.example.com
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| Shares 16 kibibytes together with one other cross-origin nested document of the same origin.
6957+
|
6958+
|
6959+
+ ---- + https://x.example.com
6960+
| Shares 16 kibibytes together with one other cross-origin nested document of the same origin.
6961+
|
6962+
+ ---- + https://ok.example.com/good
6963+
| | 64 kibibytes, granted via the "{{PermissionsPolicy/deferred-fetch}}" policy.
6964+
| |
6965+
| + ---- + https://x.example.com
6966+
| 0. Only documents with the same originas the <a for=/>top-level traversable</a> can grant
6967+
| the 8 kibibytes
6968+
|
6969+
+ ---- + https://ok.example.com/redirect, navigated to https://x.example.com
6970+
| 0. The reserved 64 kibibytes for https://ok.example.com are not available for https://x.example.com.
6971+
|
6972+
+ ---- + https://ok.example.com/back, navigated to https://me.example.com
6973+
Shares quota with the <a for=/>top-level traversable</a>, as they're same origin.
6974+
</code></pre>
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6976+
<p>In the above example, the <a for=/>top-level traversable</a> and its <a>same origin</a>
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descendants share a quota of 384 kibibytes. That value is computed as such:
6978+
<ul>
6979+
<li><p>640 kibibytes are initially granted to the <a for=/>top-level traversable</a>.
6980+
<li><p>128 kibibytes are reserved for the "{{PermissionsPolicy/deferred-fetch-minimal}}" policy.
6981+
<li><p>64 kibibytes are reserved for the container navigating to <code>https://ok.example/good</code>.
6982+
<li><p>64 kibibytes are reserved for the container navigating to <code>https://ok.example/redirect</code>, and lost when it navigates away.
6983+
<li><code>https://ok.example.com/back</code> did not reserve 64 kibibytes, because it navigated back to <a for=/>top-level traversable</a>'s origin.
6984+
<li><p>640 - 128 - 64 - 64 = 384 kibibytes.
6985+
</ul>
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</div>
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