In html styles in general, "position:sticky" (combined with other formatting) enables a div to remain visible even as the user scrolls down. (For an example of this in the Canvas UI, see the behavior of the left-hand navigation menu as you scroll down a long page.)

Using the style within the body of the Canvas page seems to have no effect, though the RCE doesn't strip it out the way it does with "forbidden" styles. I've tried applying some of the classes I found in the CSS to my divs (e.g. "ic-sticky-frame" and "sticky-toolbar") with no luck. 

Has anyone had any luck using either inline styles or existing Canvas classes to make a div "stick" to the top of the user screen, even as they scroll down the page?