eleven / messenger Public

web: no content jump on refresh — loading cover + restore open thread (#40)

Two changes so a reload lands cleanly instead of flashing an empty shell
and then jumping as messages load and scroll to the bottom:

- A full-screen loading cover (theme-coloured, matches the pre-paint bg)
  shown until the app's first real paint. boot() awaits the initial
  thread's feed load + scroll, then fades the cover out — so the first
  thing you see is the finished layout, already at the bottom.
- Remember the open thread (localStorage) and reopen it on load, so a
  refresh returns you to the same conversation. Desktop falls back to the
  first *visible* chat (skipping closed ones); "back to list" and closing
  a chat clear it. Deep-links still win.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Paul Campbell 4 months ago f83ff5b1b445c482274737a83bc86fe542d4fcc4 parent 6e86837

3 files changed, +76 −7

web/pages/index.html +4 −0
web/static/chat.js +47 −7
web/static/style.css +25 −0

diff --git a/web/pages/index.html b/web/pages/index.html

index b0fef45..7644d5b 100644

--- a/web/pages/index.html

+++ b/web/pages/index.html

@@ -37,6 +37,10 @@

</script>

+<!-- Full-screen cover shown until the app's first meaningful paint (theme bg is

+ already set pre-paint above), so a refresh doesn't flash an empty shell and

+ then jump as messages load + scroll. chat.js removes it once ready. -->

+<div id="app-loading" class="app-loading"><div class="spinner" aria-label="Loading"></div></div>

<!-- The multi-thread shell: a thread list (master) + an open thread (detail).

diff --git a/web/static/chat.js b/web/static/chat.js

index 39f4b3a..855ffa8 100644

--- a/web/static/chat.js

+++ b/web/static/chat.js

@@ -46,6 +46,7 @@ import {

} from "/static/push.js";

const SESSION_KEY = "lchat_session";

+const ACTIVE_KEY = "lchat_active"; // last-open thread id, so a refresh lands back in it

const isCoarse = matchMedia("(pointer: coarse)").matches;

const MAX_UPLOAD = 25 * 1024 * 1024; // matches maxUploadBytes (main.go)

const MAX_IMAGE_DIM = 2048; // long-edge cap; bigger images are downscaled in-browser

@@ -285,7 +286,7 @@ async function boot() {

await ensurePubkey();

await loadRoster();

await Promise.all([setupInstanceKey(), loadThreads()]);

- renderApp();

+ const opened = renderApp(); // paints the shell; opens the initial thread (async)

connectWS();

registerSW(session); // best-effort; subscribes if notifications already on

startHeartbeat();

@@ -296,14 +297,28 @@ async function boot() {

if (e.data && e.data.type === "open-thread" && e.data.thread) openThreadById(e.data.thread);

});

}

+ // Reveal only once the initial feed is loaded + scrolled — so the first paint

+ // is the finished layout, not an empty feed that then jumps to the bottom.

+ await opened;

} catch (e) {

console.error(e);

app.innerHTML =

`<div class="center"><div class="card"><h1>Something went wrong</h1>` +

`<p>Couldn't load your chats. Try reloading.</p></div></div>`;

+ } finally {

+ hideLoading();

}

+// Fade out and remove the full-screen loading cover (shown until the app's first

+// meaningful paint). Idempotent — safe to call from any entry path.

+function hideLoading() {

+ const el = document.getElementById("app-loading");

+ if (!el) return;

+ el.classList.add("hidden");

+ setTimeout(() => el.remove(), 250); // after the CSS fade

// ---- data ---------------------------------------------------------------

function ensurePubkey() {

@@ -326,6 +341,17 @@ function rosterLabel(userId) {

return e ? e.label : "Someone";

}

+// A small "BOT" tag to mark an agent in the roster picker, so it's clear before

+// you add it that it isn't a person. Self-contained styling (no CSS dependency).

+function agentTag() {

+ const t = document.createElement("span");

+ t.textContent = "BOT";

+ t.title = "This is an agent (bot), not a person";

+ t.style.cssText =

+ "margin-left:6px;font-size:0.7em;font-weight:600;letter-spacing:0.03em;padding:1px 5px;border-radius:6px;background:var(--accent,#888);color:#fff;vertical-align:middle;";

+ return t;

// The instance key is a single AES key shared by all members, used only for

// all-members content (profile photos). It's wrapped to each member's user

// pubkey (server-blind, reusing the thread-key wrap). On boot: adopt our copy if

@@ -741,16 +767,21 @@ function renderApp() {

});

renderThreadList();

- // A notification tapped while the app was closed opens with #thread=<id> —

- // land straight in it (on any platform). Otherwise desktop shows the first

- // chat; touch stays on the list.

+ // Choose the thread to land in, in priority order: a tapped-notification

+ // deep-link (#thread=), the one we were last in (so a refresh reloads where you

+ // were), else — desktop only — the first visible chat. Returns the open promise

+ // so boot() can drop the loading cover once the feed is in place (no jump).

const deep = initialThreadId();

+ let target = null;

if (deep && threads.some((t) => t.id === deep)) {

history.replaceState(null, "", location.pathname + location.search); // consume the deep link

- openThread(deep);

- } else if (!isCoarse && threads.length) {

- openThread(threads[0].id);

+ target = deep;

+ } else {

+ const saved = localStorage.getItem(ACTIVE_KEY);

+ if (saved && threads.some((t) => t.id === saved) && !hidden[saved]) target = saved;

+ else if (!isCoarse) target = (threads.find((t) => !hidden[t.id]) || {}).id || null;

}

+ return target ? openThread(target) : Promise.resolve();

}

// The thread id from a deep-link fragment (#thread=<id>), or null. Kept in the

@@ -965,6 +996,8 @@ function refreshSenderName(el) {

function showList() {

document.getElementById("tt").classList.remove("show-thread");

+ // Back to the list is the state to restore on refresh (mobile), not the thread.

+ localStorage.removeItem(ACTIVE_KEY);

}

// Header avatar: a group's photo, or the DM/self person's profile photo.

@@ -1080,6 +1113,7 @@ async function openThread(id) {

const myOpen = ++openSeq;

activeId = id;

+ localStorage.setItem(ACTIVE_KEY, id); // remember where we are, to restore on refresh

unread[id] = false;

// Opening a closed chat reopens it (locally + server, synced to your devices).

if (hidden[id]) {

@@ -2583,6 +2617,7 @@ async function closeChat() {

}).catch(() => {});

stashFeed(id); // keep its rendered feed cached for a quick reopen

activeId = null;

+ localStorage.removeItem(ACTIVE_KEY); // don't reopen a closed chat on refresh

renderThreadList();

document.getElementById("thread-view").classList.add("hidden");

document.getElementById("thread-empty").classList.remove("hidden");

@@ -2698,6 +2733,7 @@ async function leaveGroup() {

threads = threads.filter((x) => x.id !== activeId);

delete threadKeys[activeId];

activeId = null;

+ localStorage.removeItem(ACTIVE_KEY); // the thread we were in is gone

renderThreadList();

document.getElementById("thread-view").classList.add("hidden");

document.getElementById("thread-empty").classList.remove("hidden");

@@ -2805,6 +2841,7 @@ function showNewChat() {

};

const nm = document.createElement("span");

nm.textContent = e.label;

+ if (e.is_agent) nm.appendChild(agentTag());

row.appendChild(cb);

row.appendChild(nm);

list.appendChild(row);

@@ -2812,6 +2849,7 @@ function showNewChat() {

const b = document.createElement("button");

b.className = "list-row";

b.textContent = e.label;

+ if (e.is_agent) b.appendChild(agentTag());

b.onclick = () => {

const dm = existingDM(e.user_id);

if (dm) {

@@ -3157,6 +3195,7 @@ function parseLink(text) {

}

function showNoInvite() {

+ hideLoading();

app.appendChild(tpl("noinvite-tpl"));

const linkInput = document.getElementById("link");

const nameInput = document.getElementById("name");

@@ -3217,6 +3256,7 @@ function showNoInvite() {

}

function showA2HS(done) {

+ hideLoading();

app.innerHTML = "";

app.appendChild(tpl("a2hs-tpl"));

document.getElementById("a2hs-continue").onclick = () => {

diff --git a/web/static/style.css b/web/static/style.css

index 06f1380..99eabfe 100644

--- a/web/static/style.css

+++ b/web/static/style.css

@@ -138,6 +138,31 @@ html, body {

collapses to content height, and the composer floats with blank space below it. */

#app { height: 100%; }

+/* Full-screen loading cover (see index.html) — matches the pre-painted theme bg,

+ fades out once the app's first real paint is ready. */

+.app-loading {

+ position: fixed;

+ inset: 0;

+ z-index: 100;

+ display: grid;

+ place-items: center;

+ background: var(--bg);

+ transition: opacity 0.25s ease;

+.app-loading.hidden { opacity: 0; pointer-events: none; }

+.spinner {

+ width: 32px;

+ height: 32px;

+ border-radius: 50%;

+ border: 3px solid color-mix(in srgb, var(--ink) 15%, transparent);

+ border-top-color: var(--accent);

+ animation: spin 0.7s linear infinite;

+@keyframes spin { to { transform: rotate(360deg); } }

+@media (prefers-reduced-motion: reduce) {

+ .spinner { animation: none; opacity: 0.5; }

button {

font: inherit;

cursor: pointer;