Slide out block widget panels

1

Is it possible to create a slide out block widget panel like the ones Brackets.io has? For example:

brackets-inline-widget
brackets-inline-widget.png818×470 69.4 KB

If so, any pointers on how one would go about doing this? Are there any tutorials, etc.?

Thanks!

Edit

I also found this from the Brackets repo:

2

It should be, since Brackets is built on CodeMirror. I suspect they define a CSS transition for a line widget element and call changed() on the widget handle when it has finished animating.