In which direction does a screenreader read dir="rtl"?

Question

When dir="rtl" is applied to the body, the (LTR) markup does not change, but visually, it is shown right to left. When a screenreader reads this page, does it read it as it is shown (visually) or as it appears in the markup?

My concern is, although the page looks RTL, screenreaders still may not read the content in the right order.

Answer 1

After walking through an example out loud, I realized that screen readers probably read the source from top to bottom. Whether this is visually represented as Left to Right or Right to Left probably does not matter, as the first item in the source is the leftmost item in LTR and the rightmost item in RTL - either way, it's the first item that a person would read.