diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 2eb9bd8806c..9e73ab8bcf0 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -618,10 +618,12 @@ impl Document {
 
     /// Handles any updates when the document's title has changed.
     pub fn title_changed(&self) {
-        // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowsertitlechange
-        self.trigger_mozbrowser_event(MozBrowserEvent::TitleChange(String::from(self.Title())));
+        if self.browsing_context().is_some() {
+            // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowsertitlechange
+            self.trigger_mozbrowser_event(MozBrowserEvent::TitleChange(String::from(self.Title())));
 
-        self.send_title_to_compositor();
+            self.send_title_to_compositor();
+        }
     }
 
     /// Sends this document's title to the compositor.
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 72b1a3c9946..31562bc476f 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -6430,6 +6430,12 @@
             "url": "/_mozilla/mozilla/mozbrowser/mozbrowsershowmodalprompt_event.html"
           }
         ],
+        "mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html": [
+          {
+            "path": "mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html",
+            "url": "/_mozilla/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html"
+          }
+        ],
         "mozilla/mozbrowser/redirect.html": [
           {
             "path": "mozilla/mozbrowser/redirect.html",
diff --git a/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html b/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html
new file mode 100644
index 00000000000..4809f302f2f
--- /dev/null
+++ b/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event.html
@@ -0,0 +1,19 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Check if title_changed is too eager (issue #10782)</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<body></body>
+<script>
+    async_test(function(t) {
+        var iframe = document.createElement("iframe");
+        iframe.mozbrowser = "true";
+        iframe.src = "mozbrowsertitlechangedeagerly_event_iframe.html";
+        iframe.addEventListener("mozbrowsertitlechange", t.step_func(e => {
+            assert_equals(e.type, "mozbrowsertitlechange");
+            assert_not_equals(e.detail, "Bar");
+        }));
+        iframe.addEventListener("load", t.step_func_done());
+        document.body.appendChild(iframe);
+    });
+</script>
diff --git a/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event_iframe.html b/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event_iframe.html
new file mode 100644
index 00000000000..b10a632092a
--- /dev/null
+++ b/tests/wpt/mozilla/tests/mozilla/mozbrowser/mozbrowsertitlechangedeagerly_event_iframe.html
@@ -0,0 +1,16 @@
+<html>
+    <head>
+        <title>Foo</title>
+        <script>
+            var text =
+                    '<html xmlns="http://www.w3.org/1999/xhtml">' +
+                    '  <head>' +
+                    '    <title>Bar</title>' +
+                    '  </head>' +
+                    '</html>';
+            var parser = new DOMParser();
+            var doc = parser.parseFromString(text, "text/xml");
+        </script>
+    </head>
+    <body>Hello world</body>
+</html>
