demo · v130

Scroll Timeline

Chrome 130 allows multiple simultaneous scrollIntoView({ behavior: 'smooth' }) calls on independent scroll containers. Previously, a new smooth scroll cancelled any in-progress scroll in the same container — but now, selecting a chapter jumps both the outline panel and the content panel simultaneously without interruption.

Chapters

Outline (container A)

Content (container B)

Click a chapter to scroll both containers simultaneously.

Log: waiting for scroll actions…

// Chrome 130: concurrent scrollIntoView on independent containers
// Both calls start simultaneously without cancelling each other

function navigateToChapter(id) {
  const outlineEl = document.getElementById('outline-' + id);
  const contentEl = document.getElementById('content-' + id);

  // Scroll both containers at the same time ✓
  outlineEl.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
  contentEl.scrollIntoView({ behavior: 'smooth', block: 'start'  });
}

// Pre-Chrome-130 problem:
// If both elements were in the SAME scroll container,
// the second call would cancel the first smooth scroll.
// Chrome 130 fixes this: independent containers run concurrently.

see also