Do not consider edit mode as a history entry

assets/editor/main.js

@@ -140,7 +140,46 @@
     function syncContent() {
         hidden.value = view.state.doc.toString();
     }
-    form.addEventListener('submit', syncContent);
+
+    // Save POSTs via fetch and then rewrites the *editor's* history entry with
+    // the resulting page, so the edit session and its result share a single
+    // entry (see history-nav.js). A plain form submit would push a second one
+    // and leave the editor sitting in history behind the saved page.
+    //
+    // The server answers 204 + X-Target instead of a 303 because the target may
+    // carry a #section anchor the client cannot compute, and fetch drops the
+    // fragment from a followed redirect.
+    function postSave() {
+        syncContent();
+        var body = new URLSearchParams(new FormData(form)).toString();
+        fetch(form.action, {
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/x-www-form-urlencoded',
+                'X-Save-Mode': 'replace',
+            },
+            body: body,
+        }).then(function (res) {
+            if (!res.ok) {
+                return res.text().then(function (msg) {
+                    alert(msg || ('Save failed (' + res.status + ')'));
+                });
+            }
+            var target = res.headers.get('X-Target') || form.action;
+            // replaceState + reload rather than location.replace: if target
+            // differs from the current URL only by fragment the browser would
+            // skip the re-fetch and show pre-save content.
+            window.history.replaceState(null, '', target);
+            window.location.reload();
+        }).catch(function () {
+            alert('Network error — the page was not saved');
+        });
+    }
+
+    form.addEventListener('submit', function (e) {
+        e.preventDefault();
+        postSave();
+    });
 
     // --- Actions ---