frontend/packages/dashboard/src/app.js

@@ -41,28 +41,6 @@ window.marked = marked;
 
   // Helpers ($, el, esc, form, fmtAgeSecs) moved to ./common.js (#406).
 
-  // #464 — atomic-swap render helper. Each managed section's render
-  // function used to do `root.innerHTML = ''; root.append(...);` in
-  // sequence; even though both operations sit in the same JS turn,
-  // operators could still see a "blink" on every poll cycle because
-  // (a) on async paths the await yield gave the browser a paint
-  // opportunity, and (b) complex builds with many `el()` allocations
-  // can blow the browser's per-task budget enough for layout to flash
-  // empty before the new children land.
-  //
-  // The fix: build the new content off-DOM into a `DocumentFragment`,
-  // then move it into the live root in a single `replaceChildren`
-  // call. The browser never sees an intermediate empty state. Builder
-  // callbacks receive the fragment as their `root` argument, so each
-  // renderer's existing `root.append(...)` code carries over with
-  // zero internal changes. Early-return inside the builder is fine —
-  // the commit still happens with whatever the builder appended.
-  function paintAtomic(liveRoot, build) {
-    const buf = document.createDocumentFragment();
-    build(buf);
-    liveRoot.replaceChildren(buf);
-  }
-
   // Side panel singleton (Panel) moved to ./common.js (#406).
 
   // Path linkification + file-preview side panel (openFilePanel,
@@ -1849,28 +1827,26 @@ window.marked = marked;
   // agents themselves and the operator already sees them next time
   // they interact with the page.
   async function refreshReminders() {
-    const liveRoot = $('reminders-section');
+    const root = $('reminders-section');
-    if (!liveRoot) return;
+    if (!root) return;
     try {
       const resp = await fetch('/api/reminders');
       if (!resp.ok) {
-        paintAtomic(liveRoot, (root) => {
+        root.innerHTML = '';
         root.append(el('p', { class: 'empty' }, 'reminders unavailable: http ' + resp.status));
-        });
         return;
       }
       const rows = await resp.json();
       renderReminders(rows);
     } catch (err) {
-      paintAtomic(liveRoot, (root) => {
+      root.innerHTML = '';
       root.append(el('p', { class: 'empty' }, 'reminders fetch failed: ' + err));
-      });
     }
   }
   function renderReminders(rows) {
-    const liveRoot = $('reminders-section');
+    const root = $('reminders-section');
-    if (!liveRoot) return;
+    if (!root) return;
-    paintAtomic(liveRoot, (root) => {
+    root.innerHTML = '';
     if (!rows.length) {
       root.append(el('p', { class: 'empty' }, 'no queued reminders'));
       return;
@@ -1934,7 +1910,6 @@ window.marked = marked;
       ul.append(li);
     }
     root.append(ul);
-    });
   }
   function fmtDuration(secs) {
     if (secs < 60) return secs + 's';
@@ -1964,16 +1939,14 @@ window.marked = marked;
     try {
       const resp = await fetch('/api/schedules');
       if (!resp.ok) {
-        paintAtomic(listRoot, (root) => {
+        listRoot.innerHTML = '';
-          root.append(el('p', { class: 'empty' }, 'schedules unavailable: http ' + resp.status));
+        listRoot.append(el('p', { class: 'empty' }, 'schedules unavailable: http ' + resp.status));
-        });
         return;
       }
       schedulesState = await resp.json();
     } catch (err) {
-      paintAtomic(listRoot, (root) => {
+      listRoot.innerHTML = '';
-        root.append(el('p', { class: 'empty' }, 'schedules fetch failed: ' + err));
+      listRoot.append(el('p', { class: 'empty' }, 'schedules fetch failed: ' + err));
-      });
       return;
     }
     renderScheduleNewForm();
@@ -2090,15 +2063,13 @@ window.marked = marked;
   }
 
   function renderScheduleNewForm() {
-    const liveRoot = $('schedule-new-section');
+    const root = $('schedule-new-section');
-    if (!liveRoot) return;
+    if (!root) return;
     // Preserve any field the operator was mid-typing in by reading
     // current values before we re-render. Only `body` + `description`
     // are big enough to feel — the others are toggle/datetime/number.
-    // Read from the live root BEFORE the swap so we see current
+    const carry = readScheduleFormCarry(root);
-    // values (the fragment we build into is fresh).
+    root.innerHTML = '';
-    const carry = readScheduleFormCarry(liveRoot);
-    paintAtomic(liveRoot, (root) => {
 
     // Targets multi-select pulls from the live containers list. The
     // backend accepts any string (forward-compat for richer recipients),
@@ -2194,7 +2165,6 @@ window.marked = marked;
     form_.append(actions);
 
     root.append(form_);
-    });  // paintAtomic
   }
   function readScheduleFormCarry(root) {
     return {
@@ -2279,9 +2249,9 @@ window.marked = marked;
     }
   }
   function renderSchedulesList() {
-    const liveRoot = $('schedules-section');
+    const root = $('schedules-section');
-    if (!liveRoot) return;
+    if (!root) return;
-    paintAtomic(liveRoot, (root) => {
+    root.innerHTML = '';
     if (!schedulesState.length) {
       root.append(el('p', { class: 'empty' }, 'no schedules queued'));
       return;
@@ -2296,7 +2266,6 @@ window.marked = marked;
     });
     for (const s of sorted) ul.append(renderScheduleCard(s));
     root.append(ul);
-    });
   }
   function renderScheduleCard(s) {
     const cancelled = !!s.cancelled_at_unix;