Using GarageSale Version 7.0.14b2 (830), macOS Version 10.12.6 (16G1212)
In Editor Mode, the description field text is cutoff on the right side by the disabled scrollbar, so just hide/remove the description text field scrollbar, if it is not needed and disabled. Just like in Preview Mode. And re-flow text so it does not get cutoff when the scrollbar is actually needed and added and enabled.