This makes it very hard to enter the right number of coins when selling them to Crassus.
You can enter digits but cannot delete them or change the entry position unless you've realized that you have to use Delete instead of Backspace.
As some people suggested for some reason right-to-left text editing (used in Korea btw) turned on for me, not sure why, in this window. So it might not repro for others, but repros for me even after restarting the game.