diff --git a/crates/ui-egui/src/app.rs b/crates/ui-egui/src/app.rs
index 23bee9babc..352178bb7b 100644
--- a/crates/ui-egui/src/app.rs
+++ b/crates/ui-egui/src/app.rs
@@ -546,14 +546,23 @@ impl eframe::App for PdfCraftApp {
         for view in &mut self.views {
             view.begin_render_frame();
         }
-        // The window shows the active document's name (or title, if it asks for that).
+        // The window shows the active document's name (or title, if it asks for that), with •
+        // while it has unsaved changes, as the other Craft apps write it (#3640).
+        let view = self.active.and_then(|i| self.views.get(i));
+        let dirty = view.and_then(|v| self.session.get(v.id)).is_some_and(|d| d.dirty);
+        let mark = if dirty { " •" } else { "" };
         let title = self
             .active
             .and_then(|i| crate::canvas::tab_label(self, i))
             .or_else(|| self.combine_showing().then(|| tl!("Combine files").to_owned()))
-            .map_or_else(|| "PdfCraft".to_owned(), |name| format!("{name} — PdfCraft"));
+            .map_or_else(|| "PdfCraft".to_owned(), |name| format!("{name}{mark} — PdfCraft"));
         if title != self.window_title {
             ctx.send_viewport_cmd(egui::ViewportCommand::Title(title.clone()));
+            // eframe's web runner ignores Title: set the page's own, which an embedding host reads.
+            #[cfg(target_arch = "wasm32")]
+            if let Some(document) = web_sys::window().and_then(|w| w.document()) {
+                document.set_title(&title);
+            }
             self.window_title = title;
         }
         // The accessible window takes the same name, so a screen reader (AT-SPI on Linux, UIA on
diff --git a/crates/ui-egui/tests/it/accessibility.rs b/crates/ui-egui/tests/it/accessibility.rs
index 7d13df6adc..eebfc40020 100644
--- a/crates/ui-egui/tests/it/accessibility.rs
+++ b/crates/ui-egui/tests/it/accessibility.rs
@@ -91,7 +91,7 @@ fn checking_fixing_skipping_and_reporting() {
     assert_eq!(status(&h, Rule::Title), Status::Passed);
     assert_eq!(h.state().a11y.previous.as_ref().unwrap().1.result(Rule::Title).unwrap().status, Status::Failed);
     assert!(matches!(h.state().dialog, Some(Dialog::Properties(_))));
-    assert_eq!(h.state().window_title, "notes — PdfCraft");
+    assert_eq!(h.state().window_title, "notes • — PdfCraft");
     h.state_mut().dialog = None;
     h.run_steps(2);
     h.get_by_label("Compare");
diff --git a/crates/ui-egui/tests/it/viewer.rs b/crates/ui-egui/tests/it/viewer.rs
index f2a12b69aa..0db837f901 100644
--- a/crates/ui-egui/tests/it/viewer.rs
+++ b/crates/ui-egui/tests/it/viewer.rs
@@ -974,10 +974,36 @@ fn tab_and_window_show_the_document_title_when_asked() {
         s.session.apply(id, Edit::SetInitialView(Box::new(v))).unwrap();
     }
     h.run_steps(2);
-    assert_eq!(h.state().window_title, "Quarterly report — PdfCraft");
+    // The edits are unsaved, so the title says so (#3640).
+    assert_eq!(h.state().window_title, "Quarterly report • — PdfCraft");
     h.get_by_label_contains("Quarterly report");
 }
 
+#[test]
+fn the_window_title_marks_unsaved_changes_until_saved() {
+    use pdfcraft_engine::Edit;
+    let mut h = harness();
+    h.run_steps(2);
+    assert_eq!(h.state().window_title, "b.pdf — PdfCraft");
+    {
+        let s = h.state_mut();
+        let id = s.views[s.active.unwrap()].id;
+        s.session.apply(id, Edit::SetInfo { key: "Subject".into(), value: "Budget".into() }).unwrap();
+    }
+    h.run_steps(2);
+    assert_eq!(h.state().window_title, "b.pdf • — PdfCraft", "unsaved changes (#3640)");
+    // Saved under its own name, so the title changes only by the mark.
+    let dir = std::env::temp_dir().join(format!("pdfcraft-title-dirty-{}", std::process::id()));
+    std::fs::create_dir_all(&dir).unwrap();
+    h.state_mut().save_override = Some(dir.join("b.pdf").to_string_lossy().into_owned());
+    assert!(h.state_mut().execute("file.save"));
+    h.run_steps(2);
+    let _ = std::fs::remove_dir_all(&dir);
+    let s = h.state();
+    assert!(!s.session.get(s.views[s.active.unwrap()].id).unwrap().dirty);
+    assert_eq!(s.window_title, "b.pdf — PdfCraft", "saved");
+}
+
 #[test]
 fn a_placeholder_title_leaves_the_file_name_on_the_tab_and_window() {
     // A browser's "Save as PDF" of a blank page or pop-up titles the document "about:blank"
@@ -993,7 +1019,7 @@ fn a_placeholder_title_leaves_the_file_name_on_the_tab_and_window() {
         s.session.apply(id, Edit::SetInitialView(Box::new(v))).unwrap();
     }
     h.run_steps(2);
-    assert_eq!(h.state().window_title, "b.pdf — PdfCraft");
+    assert_eq!(h.state().window_title, "b.pdf • — PdfCraft");
     assert!(h.query_by_label_contains("about:blank").is_none());
 }
 
@@ -2265,6 +2291,7 @@ fn the_accessible_window_has_the_window_title_as_its_name() {
         s.session.apply(id, Edit::SetInitialView(Box::new(v))).unwrap();
     }
     h.run_steps(2);
-    assert_eq!(name(&h).as_deref(), Some("Quarterly report — PdfCraft"));
+    // Unsaved, so it carries the window title's mark too (#3640).
+    assert_eq!(name(&h).as_deref(), Some("Quarterly report • — PdfCraft"));
     assert_eq!(name(&h), Some(h.state().window_title.clone()));
 }