The Popover API introduced in Baseline 2024 provides developers with a consistent way to display popover content on web pages. Popovers can be controlled using HTML attributes or JavaScript and are a common way to draw attention to important information or actions. Popovers created with the API are always non-modal, but elements can be used for modal popovers. Unique features include combining popover control with dialog semantics and creating popovers using new HTML attributes or a JavaScript API. CSS features like ::backdrop and :popover-open enhance popover styling and functionality. Overall, the Popover API offers a versatile tool for creating interactive elements on web pages.
https://developer.mozilla.org/en-US/docs/Web/API/Popover_API