Asynchronous or async loading refers to downloading and applying a page resource in the background, independently of other resources and without otherwise impacting the initial loading process. Terms & Techniques The terms lazy loading, on-demand, deferred, and asynchronous are all related to the various methods for minimizing initial-load page weight and eliminating render blocking resources. ... Eliminate Render-blocking CSS to Increase Google PageSpeed Score

If you are working in a web development inputs or textarea or div, you might need to create a button like "Copy to Clipboard" to copy all contents of input or div to user's clipboard for making it better for UI