1 files changed, 44 insertions, 6 deletions
diff --git a/src/features/messages.js b/src/features/messages.js
index 2580ed9..9cba810 100644
--- a/src/features/messages.js
+++ b/src/features/messages.js
@@ -11934,12 +11934,48 @@ export function messagesFeature(ctx) {
     let tries = 0;
     const go = () => {
       if (ui.mediaPager || !document.querySelector('.notes-feed')) { if (++tries < 90) requestAnimationFrame(go); return; }
-      const list = c.winList ? c.winList() : c.notes;
-      const i = list.findIndex((e) => e.id === rowId);
-      if (i >= 0) glideToPost(c, list, i);
+      landOnPost(c, rowId);
     };
     requestAnimationFrame(go);
   }
+  // Put the feed on a post the reader hasn't been near — one the pager went
+  // on to, maybe paged in while it was open and never drawn. Its place is
+  // only a guess until it is drawn, and the rows around it settle as they
+  // draw (a long post, a picture finding its size), so: jump to the guess,
+  // draw, and set the row under the top again each frame — until it has sat
+  // still a moment, a couple of seconds have gone, or the reader touches the
+  // page. A jump, not a glide: the pager was covering the feed.
+  function landOnPost(c, rowId) {
+    const MARGIN = 8, t0 = Date.now();
+    const find = () => document.querySelector('.notes-feed > [data-key="' + CSS.escape(rowId) + '"]');
+    let still = 0, misses = 0, lastY = null;
+    const step = () => {
+      if (c !== feed || ui.mediaPager || !document.querySelector('.notes-feed') || lastInputAt > t0 || Date.now() - t0 > 2500) return;
+      // the page sent somewhere else meanwhile (not by a finger: a glide, a link)
+      if (lastY !== null && Math.abs(window.scrollY - lastY) > window.innerHeight / 2) return;
+      const el = find();
+      if (!el) {
+        const list = c.winList ? c.winList() : c.notes;
+        const i = list.findIndex((e) => e.id === rowId);
+        if (i < 0 || ++misses > 20) return;
+        let sum = 0, n = 0;
+        for (const v of (c.heights || new Map()).values()) { sum += v; n++; }
+        const avg = n ? sum / n : 200;
+        let y = 0;
+        for (let j = 0; j < i; j++) y += ((c.heights && c.heights.get(list[j].id)) || avg) + ROW_GAP;
+        window.scrollTo(0, Math.max(0, (c.listTop || 0) + y - MARGIN));
+        render();
+        requestAnimationFrame(step);
+        return;
+      }
+      const off = el.getBoundingClientRect().top - MARGIN;
+      if (Math.abs(off) > 2) { window.scrollTo(0, Math.max(0, window.scrollY + off)); still = 0; }
+      else if (++still >= 20 && Date.now() - t0 > 600) return;
+      lastY = window.scrollY;
+      requestAnimationFrame(step);
+    };
+    step();
+  }
   // Leaving the pager for another page (a profile, sign-in, the zap amount):
   // only the feed's own render syncs the pager, and those pages don't paint
   // the feed — so the overlay goes now, not on the next feed render.
@@ -12262,11 +12298,13 @@ export function messagesFeature(ctx) {
   }
   // A pager opened from the feed walks the feed's own posts, which page in
   // ten at a time as the feed is scrolled. Swiping is the scrolling here:
-  // with only a few slides left past the one on screen, the feed pages on
+  // with only a few slides left past the one on screen (PAGER_AHEAD), the feed pages on
   // (the posts it holds, then older ones from the relays) until there are
   // more — several pages if those posts carry none. A page that brings
   // nothing (the feed busy, or at its end) stops it; the tick tries again.
-  const PAGER_AHEAD = 3;
+  // how many slides ahead to keep: clips are fewer and further between
+  // (more pages to find the next) and each is watched a while, so further
+  const PAGER_AHEAD = { images: 4, videos: 6 };
   let pagerFeeding = false;
   async function pagerFeedAhead() {
     if (pagerFeeding || !pager || !pager.fromFeed) return;
@@ -12275,7 +12313,7 @@ export function messagesFeature(ctx) {
       const c = feedNow();
       for (let pages = 0; pages < 8 && pager && pager.fromFeed; pages++) {
         const slides = [...pager.scroller.children];
-        if (slides.length - 1 - slides.indexOf(pager.cur) > PAGER_AHEAD) break;
+        if (slides.length - 1 - slides.indexOf(pager.cur) > (PAGER_AHEAD[pager.kind] || 4)) break;
         const shown = c.shown, held = c.notes.length;
         await loadOlderFeed();
         growPager();