From a130c14d16a34a1983ea00cfe283c24a107e3cfe Mon Sep 17 00:00:00 2001
From: Ben Vinegar <ben@benv.ca>
Date: Sun, 5 Jul 2026 14:32:48 -0400
Subject: [PATCH] feat(viewer): show recent revision indicator

---
 .changeset/fresh-dots-dance.md |  5 +++++
 viewer/src/Card.tsx            | 29 +++++++++++++++++++++++++
 viewer/src/styles.css          | 39 ++++++++++++++++++++++++++++++++++
 3 files changed, 73 insertions(+)
 create mode 100644 .changeset/fresh-dots-dance.md

diff --git a/.changeset/fresh-dots-dance.md b/.changeset/fresh-dots-dance.md
new file mode 100644
index 0000000..628764a
--- /dev/null
+++ b/.changeset/fresh-dots-dance.md
@@ -0,0 +1,5 @@
+---
+"sideshow": patch
+---
+
+Show a pulsing sidecar dot next to the version pill when a post revision was updated recently.
diff --git a/viewer/src/Card.tsx b/viewer/src/Card.tsx
index 8224719..9cbf7de 100644
--- a/viewer/src/Card.tsx
+++ b/viewer/src/Card.tsx
@@ -71,6 +71,7 @@ export function frameForSource(source: unknown): { id: string; iframe: HTMLIFram
 // one line, max generous enough for a long diff/markdown without runaway growth.
 const MIN_FRAME_H = 24;
 const MAX_FRAME_H = 4000;
+const RECENT_UPDATE_MS = 2 * 60 * 1000;
 export function applyFrameHeight(iframe: HTMLIFrameElement, reportedHeight: unknown): void {
   iframe.style.height = Math.min(Math.max(Number(reportedHeight), MIN_FRAME_H), MAX_FRAME_H) + "px";
 }
@@ -185,6 +186,7 @@ export function Card(props: { post: Post; standalone?: boolean }) {
   const [annotating, setAnnotating] = createSignal(false);
   const [anchorDraft, setAnchorDraft] = createSignal<CommentAnchor | null>(null);
   const [fullscreenSurface, setFullscreenSurface] = createSignal<FullscreenSurface | null>(null);
+  const [recentUpdateNow, setRecentUpdateNow] = createSignal(Date.now());
   let stopPoll: (() => void) | undefined;
 
   const surfaceTitle = (surfaceIndex: number) =>
@@ -200,6 +202,15 @@ export function Card(props: { post: Post; standalone?: boolean }) {
   const anchoredComments = (surfaceIndex: number) =>
     comments().filter((c) => c.postId === props.post.id && c.anchor?.surfaceIndex === surfaceIndex);
 
+  const isRecentRevision = () => {
+    const updatedAt = new Date(props.post.updatedAt).getTime();
+    return (
+      props.post.version > 1 &&
+      Number.isFinite(updatedAt) &&
+      recentUpdateNow() - updatedAt < RECENT_UPDATE_MS
+    );
+  };
+
   const closeFullscreen = () => {
     const opener = fullscreenOpener;
     fullscreenOpener = undefined;
@@ -241,6 +252,20 @@ export function Card(props: { post: Post; standalone?: boolean }) {
   createEffect(scrollIfTarget);
   onCleanup(() => stopPoll?.());
 
+  createEffect(() => {
+    const version = props.post.version;
+    const updatedAt = new Date(props.post.updatedAt).getTime();
+    if (version <= 1 || !Number.isFinite(updatedAt)) return;
+
+    const now = Date.now();
+    setRecentUpdateNow(now);
+    const remaining = RECENT_UPDATE_MS - (now - updatedAt);
+    if (remaining <= 0) return;
+
+    const timer = setTimeout(() => setRecentUpdateNow(Date.now()), remaining + 50);
+    onCleanup(() => clearTimeout(timer));
+  });
+
   createEffect(() => {
     if (!fullscreenSurface()) return;
     queueMicrotask(() => fullscreenCloseButton?.focus());
@@ -350,6 +375,10 @@ export function Card(props: { post: Post; standalone?: boolean }) {
                 </select>
               )}
             </Show>
+            <Show when={isRecentRevision()}>
+              <span class="update-dot" title="updated just now" aria-hidden="true"></span>
+              <span class="update-status">updated recently</span>
+            </Show>
           </span>
           <span class="sp"></span>
           <span class="card-meta">{relTime(props.post.updatedAt)}</span>
diff --git a/viewer/src/styles.css b/viewer/src/styles.css
index 4f7f365..aeadcf5 100644
--- a/viewer/src/styles.css
+++ b/viewer/src/styles.css
@@ -514,6 +514,12 @@ main {
   font-weight: 500;
   font-size: 14px;
 }
+.card-head .vslot {
+  display: inline-flex;
+  align-items: center;
+  gap: 5px;
+  white-space: nowrap;
+}
 .vbadge {
   font-size: 11px;
   color: var(--muted);
@@ -529,6 +535,36 @@ select.vbadge {
   cursor: pointer;
   appearance: none;
 }
+.card-head .update-dot {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: var(--accent);
+  box-shadow: 0 0 0 3px var(--accent-bg);
+  animation: update-dot-pulse 1.6s ease-out infinite;
+}
+.card-head .update-status {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  margin: -1px;
+  overflow: hidden;
+  clip: rect(0, 0, 0, 0);
+  white-space: nowrap;
+  border: 0;
+}
+@keyframes update-dot-pulse {
+  0%,
+  100% {
+    opacity: 1;
+    transform: scale(1);
+  }
+  60% {
+    opacity: 0.48;
+    transform: scale(0.82);
+  }
+}
 .card-meta {
   font-size: 12px;
   color: var(--faint);
@@ -1860,6 +1896,9 @@ iframe {
   color: var(--accent);
 }
 @media (prefers-reduced-motion: reduce) {
+  .card-head .update-dot {
+    animation: none;
+  }
   .topbar .menu,
   aside,
   #scrim,