HTML Browser Support
Plan a fallback for a browser without the popover feature.
Understand the topic
Browser support depends on the feature, browser version, device, and context. Basic HTML is widely implemented, but newer attributes and APIs can have gaps. Consult compatibility tables, use feature detection for enhancements, and test the actual target browsers. A polyfill may reproduce some behavior, but it does not automatically provide correct semantics or every native capability.
Worked example
<p id="popover-support" role="status"></p>
<script>
document.querySelector("#popover-support").textContent =
"popover" in HTMLElement.prototype ? "Popover interface detected." : "Provide a visible help fallback.";
</script>The test checks interface exposure. It does not replace testing actual behavior, keyboard access, and fallback presentation.
Practice
Plan a fallback for a browser without the popover feature.
Show a suggested answer
Keep essential help available in ordinary content or a details disclosure, and enhance it with a popover only when supported.Common mistake
Do not use browser-name sniffing as your first solution. Feature detection and compatibility testing are usually more useful.