Test Anchor (mit Polyfill von oddbird)

<style>
	[popover] {
		top: anchor(top);
		left: anchor(right);
		margin: 0;
	}
	#d1 , #d2, #d3 {
		position-anchor: auto;
	}

	#b4 {
		anchor-name: --b4
	}

	#d4 {
		position-anchor: --b4;
	}

	.toggle-button {
		anchor-name: --toggle-button;
	}

	#d5, #d6 {
		position-anchor: --toggle-button;
	}

</style>
	

<div>
	<button popovertarget="d1" popovertargetaction="toggle">V1</button>
	<div id="d1" popover>V1</div>
</div>

<div>
	<button popovertarget="d2" popovertargetaction="toggle">V2</button>
	<div id="d2" popover anchor>V2</div>
</div>

<div>
	<button id="b3" popovertarget="d3" popovertargetaction="toggle">V3</button>
	<div id="d3" popover anchor="b3">V3</div>
</div>

<div>
	<button id="b4" popovertarget="d4" popovertargetaction="toggle">V4</button>
	<div id="d4" popover>V4</div>
</div>

<div>
	<button id="b5" class="toggle-button" popovertarget="d5" popovertargetaction="toggle">V5</button>
	<div id="d5" popover>V5</div>
</div>

<div>
	<button id="b6" class="toggle-button" popovertarget="d6" popovertargetaction="toggle">V6</button>
	<div id="d6" popover>V6</div>
</div>