Proposal: Multiple user script worlds (#560)

SHA: 5869199
Reason: push, by Rob--W

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

specification/window.browser.html

@@ -7,7 +7,7 @@
   <link href="https://www.w3.org/StyleSheets/TR/2021/cg-draft" rel="stylesheet">
   <meta content="Bikeshed version 82ce88815, updated Thu Sep 7 16:33:55 2023 -0700" name="generator">
   <link href="https://w3c.github.io/webextensions/specification/window.browser.html" rel="canonical">
-  <meta content="d99619c0b72b8bcd4c87b628755683080a233dfc" name="document-revision">
+  <meta content="5869199abf154983fe458f01d44a6e330dc30fa5" name="document-revision">
 <style>/* Boilerplate: style-autolinks */
 .css.css, .property.property, .descriptor.descriptor {
     color: var(--a-normal-text);
@@ -723,8 +723,8 @@ <h3 class="heading settled" id="introduction"><span class="content">Introduction
   and are left up to User Agent implementation.</p>
    </section>
    <section>
-    <h3 class="heading settled" id="window-interface"><span class="content"> <a class="idl-code" data-link-type="attribute" href="#dom-window-browser" id="ref-for-dom-window-browser"><code>window.browser</code></a> API </span></h3>
-    <p><code class="idl"><a data-link-type="idl" href="#dom-serviceworkerglobalscope-browser" id="ref-for-dom-serviceworkerglobalscope-browser">browser</a></code> is UA defined attribute exposed on <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window" id="ref-for-dom-window">window</a></code>. When implemented,
+    <h3 class="heading settled" id="window-interface"><span class="content"> <a class="idl-code" data-link-type="attribute" href="#dom-serviceworkerglobalscope-browser" id="ref-for-dom-serviceworkerglobalscope-browser"><code>window.browser</code></a> API </span></h3>
+    <p><code class="idl"><a data-link-type="idl" href="#dom-window-browser" id="ref-for-dom-window-browser">browser</a></code> is UA defined attribute exposed on <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-window" id="ref-for-dom-window">window</a></code>. When implemented,
     it MUST be used only for WebExtension related functionality.</p>
    </section>
 <pre class="idl highlight def"><c- b>partial</c-> <c- b>interface</c-> <a class="idl-code" data-link-type="interface" href="https://html.spec.whatwg.org/multipage/nav-history-apis.html#window" id="ref-for-window"><c- g>Window</c-></a> {