The Grid Widget will display any text content as HTML (provided there is no conflict with the page structure, styles, scripts, etc).
There is no clear boundaries of what is supported and what might break a dashboard, and you should make tests for the HTML features you want to use.
Your data contains a text field (called “html” here) with some HTML markup :
You can bind this field in the Grid :
… and the HTML will be interpreted :
(this is from the same data as above)
This can be used for many customization cases, including displaying animated GIFs conditionally :