Tooltips that follow targets with anchor-name and position-area Dropdowns and select menus paired with the Popover API for zero JS Inline edit popovers that respect viewport edges via position-try Context menus from one shared anchor with fallback chains Follow-cursor labels in dashboards that survive scroll When to pick Anchor Positioning over Floating UI or hand-rolled JS I have spent more years than I want to count writing JavaScript that calculates where a tooltip should sit. Measure the trigger, measure the viewport, measure the panel, flip when you run out of room, reposition on scroll, reposition on resize, kill it all when the page navigates. Every dropdown, popover, and context menu was the same dance. Floating UI cleaned up a lot of that pain, and I shipped it for years, but it was still a runtime tax of measure-then-paint that sometimes flickered on first frame. Then CSS Anchor Positioning landed in Chrome 125 in May 2024, and by April 2026 Safari 26 and Firefox 127+ both ship the full spec.…