You might have observed on some sites showing an image, video, logo or anything with some embed code with a click to copy button. Mostly these types of Grab box are found in non-profit sites promoting any cause or campaign, it was widely used in SOPA-PIPA potests. You can use this type of widget in your WordPress site too by following few simple steps given here.
The widget displays a textarea showing your code for your readers to copy-paste in their blogs etc. The widget will even automatically generate the correct code for you, simply fill in fields in the widget and click Save.