I believe desktop Stacks is only a version old (10.14) so you probably haven't been missing it for too long fortunately. Another good tip for screenshots is disabling the floating thumbnail. Just open the screenshot app and disable it in the options menu.
On the topic of screenshots, one I didn’t know was hitting space before you take a screenshot will make it capture an entire Window, including the shadow instead of having to drag a region
Plus holding option while you click takes a screenshot without the shadow, which I find vastly preferable. I only found out about that a couple of months ago, after a long time being annoyed.
