Look! The popover is available in all major browsers now, starting from this week’s Firefox 125 release 🥹 This includes HTML attributes, CSS pseudo-classes, and JS API.

Firefox 125 release notes https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/125

Popover API on MDN https://developer.mozilla.org/en-US/docs/Web/API/Popover_API