When I have set show-mode-in-prompt on in my .inputrc, starting a pry session (for me currently with rails c) does not show a command prompt or any characters I type in.
Commenting this line out fixes the issue, but it would be nice to be able to leave it on so I can do nice bash things.
(current bash: GNU bash, version 5.1.4(1)-release (aarch64-unknown-linux-gnu))