Hi, this also bugs me. But ksh is not bash. Try hitting ESC before an arrow. (I'm not sure if it is a consistent keystroke behavior of ksh or not)
Here's one of older threads to this: https://marc.info/?t=121265339800001&r=1&w=2 regards, Michal Bozon Dave Cohen wrote:
... I'll try to describe an annoyance with my ksh setup. Web and man page searching has not provided a solution. I'm relatively new to both ksh and openbsd. I'm on version 5.9 release. Problem happens when I navigate command history with ctrl-r, then use left or right arrow. Hitting left arrow writes "[D", right inserts "[C". I'm hitting the arrow keys so I can edit my prior command. It's a habit I'm used to that works in bash. ...