Responsive oEmbed is a free WordPress plugin designed to enhance the display of embedded content from platforms like YouTube, Vimeo, and Soundcloud. It achieves this by applying minimal CSS rules and wrapping HTML elements to maintain the correct aspect ratio of oEmbed elements. This ensures that multimedia content is displayed correctly across different devices, improving the user experience.

Notably, the plugin is compatible with the Classic Editor but does not function with the Gutenberg editor due to conflicting CSS. It calculates the aspect ratio based on the width and height attributes of the embedded elements. However, it only works when both attributes are present and does not support oEmbeds that rely on JavaScript for dimension calculations.