demo · v133
Popover invoker anchor
The element with popovertarget is now implicitly the popover's anchor - no explicit anchor-name needed. Pick a position-area and the menu jumps relative to the invoker button.
checking support...
the HTML/CSS
<button popovertarget="menu">open</button>
<div popover id="menu">...</div>
#menu {
position-area: block-end; /* uses the implicit invoker anchor */
position-try-fallbacks: flip-block;
}