New posts go in above the first post at the top of the feed

Arrivals used to wait behind the pill whenever the feed header was on
screen. They now go in above the first post with that post held where
it is, so the page grows upward and can be scrolled to before tapping
the pill. While the composer or another header field is in use they
still wait. The pill clears only when the reader scrolls up to the
newest post, not on the hold's own downward correction.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 7 insertions, 5 deletions

diff --git a/tools/feed-streaming-test.js b/tools/feed-streaming-test.js
index 4295243..e662b42 100644
--- a/tools/feed-streaming-test.js
+++ b/tools/feed-streaming-test.js
@@ -136,13 +136,15 @@ try {
   await page.close();
 
   page = await visit();
-  const headerTop = await page.$eval('.chat-page > .row', (r) => r.getBoundingClientRect().top);
+  const firstKey = await page.$eval('.notes-feed > .row[data-key]', (r) => r.getAttribute('data-key'));
+  const firstTop = await page.$eval(row(firstKey), (r) => r.getBoundingClientRect().top);
   await page.evaluate((evs) => window.deliver(evs), [fast, later]);
   await page.waitForFunction(() => document.querySelector('.feed-new-pill .n')?.textContent === '2', { timeout: 2000 });
-  assert(!(await page.$(row(fast.id))), 'header-visible prepends wait for an explicit tap');
-  assert.equal(await page.$eval('.chat-page > .row', (r) => r.getBoundingClientRect().top), headerTop);
-  await page.evaluate(() => { scrollTo(0, 1); scrollTo(0, 0); });
-  assert.equal(await count(page), 2, 'scrolling at the top does not clear deferred new posts');
+  await page.waitForSelector(row(fast.id), { timeout: 2000 });
+  // header showing: they go in above the first post, which doesn't move
+  assert(Math.abs(await page.$eval(row(firstKey), (r) => r.getBoundingClientRect().top) - firstTop) <= 1, 'header-visible prepends hold the first post still');
+  assert(await page.evaluate(() => scrollY > 0), 'the page is scrolled by what went in above');
+  assert.equal(await count(page), 2, 'the pill still says how many are up there');
   await page.click('.feed-new-pill');
   await page.waitForSelector(row(later.id));
   assert(await page.$eval(row(later.id), (r) => Math.abs(r.getBoundingClientRect().top - 8) <= 2), 'tap reveals the oldest ready new post');