The video pager never puts up a stand-in still: a clip joins the carousel only once its own first frame is on its slide.

Where the server had no first frame for a clip, its slide showed the post's still (a kept frame or the post's picture) and swapped it for the clip's first frame when one came — often a different picture, and the swap jarred (Adam, 2026-10-17: "i don't want to show posters and then switch to the first frame because sometimes the poster and first frame were not the same and that was jarring. could we just always wait until we have a non-black frame before including the video in the pager?"). Now such a clip gets no picture at all and waits out of the carousel until its first frame is drawn from its cached opening as the clip ahead; one with no frame to be had stays out. The clip tapped to open the pager is unchanged.

tools/pager-first-frame-test.js: the clip without a server frame has no stand-in and waits out of the carousel, then gets its drawn frame. pager-ready-gate, pager-no-poster, pager-eager, pager-loading and pager-swipe-fly pass.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_013ZDf1cyCQLkfjftYhymZAg

1 files changed, 8 insertions, 8 deletions

diff --git a/src/features/messages.js b/src/features/messages.js
index 326c420..0ea7520 100644
--- a/src/features/messages.js
+++ b/src/features/messages.js
@@ -12893,21 +12893,23 @@ export function messagesFeature(ctx) {
   // it starts playing"). The server's first frame (vmedia first.jpg: frame
   // 0 at full size, any host, any layout, cached at the CDN) is the first
   // choice, fetched and decoded aside and put on the slide when it is
-  // ready; the frame drawn here is the fallback for the next clip; a clip
-  // with neither keeps the still there is (a kept frame, the post's
-  // picture), soft but not black, replaced by a first frame when one comes.
+  // ready; the frame drawn here is the fallback for the next clip. A clip
+  // with neither gets no picture at all — and so stays out of the carousel
+  // (pagerReveal): the post's own still, put up meanwhile, was often not
+  // the clip's first frame, and the swap from one to the other jarred
+  // (Adam, 2026-10-17: "i don't want to show posters and then switch to
+  // the first frame … could we just always wait until we have a non-black
+  // frame before including the video in the pager?").
   function slideFrame(s, k) {
     const v = s.querySelector('video.mp-media');
     if (!v || v._frame === 'first' || v._frameBusy) return;
     const url = v.getAttribute('data-src');
     const put = (p, kind) => {
       if (!p || !pager || !s.isConnected || v._frame === 'first') return false;
-      if (kind === 'soft' && (v._frame || pager.cur === s)) return false; // never a soft still under the clip on screen
       v.setAttribute('poster', p); v._frame = kind;
       pagerReveal();
       return true;
     };
-    const soft = () => put(videoThumbs.get(url) || posterOf(s._ev, url), 'soft');
     const first = serverFirst(url);
     if (first && !serverFirstFailed.has(url)) {
       v._frameBusy = true;
@@ -12926,10 +12928,8 @@ export function messagesFeature(ctx) {
     if (k === 0 && !v._grabbed) { // the next clip: its opening is in the cache, the frame comes from there
       v._grabbed = true;
       v._frameBusy = true;
-      pagerPoster(playSrc(url)).then((p) => { v._frameBusy = false; if (!put(p, 'first')) soft(); });
-      return;
+      pagerPoster(playSrc(url)).then((p) => { v._frameBusy = false; put(p, 'first'); });
     }
-    if (first) soft(); // (the server had none: the still, if any, rather than black)
   }
   // The opening of a clip about to be reached, fetched into the browser's
   // HTTP cache with a range request: the player's own request for the file