The 'inert' HTML Attribute

Today I learned about a relatively new HTML attribute that received full browser compatibility back in April 2023. That attribute is inert. This property is valuable when you want to make your webpage or app more navigable via the keyboard, particularly when you have offscreen elements. For example, elements in a sidebar. Add the inert attribute to a container and everything inside the container will no longer be interactive with the keyboard or mouse.

You can find more information at the MDN info page.