I've got the exact same issue. I just noticed this issue in the past week.
Version 2.6.2 (262912)
As you state, you type the text and once you submit what you have typed, it flips upside down. I have also found it is not all characters. For instance I was numbering a screenshot with '1', '2', and '3' and the '3' showed right-side-up but the others did not. In either case it cut off the bottom half of the text as well.