Not being able to select the right key when there are several keys.

In Manual Encryption, you can assign emails for which you want to use a particular key.

• On MacOS, you can do this via Canary Mail > Preferences > Security > Keys > Click on 'Details' for the key you want to assign the emails > Add the email addresses under 'USE FOR EMAILS'. 

• On iOS, you can do this via Canary > Settings > Security > Encryption Mode > Keys > Select the key > Add the email addresses under 'USE FOR EMAILS'.