JAWS not visually scrolling `overflow:scroll` and `<iframe>` content correctly

Summary

Go to a page that contains a scrolling container (using overflow:scroll) or an embedded frame (<iframe>)
In browse mode, read through the page, and read through the content of the scrolling container/embedded frame

Expected result

Reading through the scrolling container or iframe, I'd expect the latter to visually scroll along with the position of the screen reader focus / reading cursor. While not always perfect, NVDA seems to do a much better job of trying to visually scroll these to keep them roughly in sync visually/aurally.

Actual result

The scrolling container and embedded frame only scroll much later (effectively, the screen reader focus "disappears" out of the boundaries of the scroller/iframe, and a visible scroll only happens when the reading cursor would effectively be hitting the top or bottom of the actual browser window).