http://ssd.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/ps/module/how-use-otr-macos
For each entry, expand it by clicking the gray triangle, and then click the newly-exposed line that say "Display a notification," then click the minus icon ("-") at the lower left to remove that line." If you are worried about records left on your computer, you should also turn on full-disk encryption, which will help protect this data from being obtained by a third party without your password.