When in the Account Settings, where all email templates are on display, I cannot save the page form, because the message 'token' is not a supported key. occurs.
I just used composer to install the module and enabled it via drush en rest_password. After that I went straight to the restui enabled both /user/list-password and /user/lost-password-reset. After that I went to the Account Settings and noticed the existence of the new email template and tried to save (no changes) and got presented with the error message.
I did an drush config:export to see which "token" key it could be. The module adds an 'token' to the email settings. Idk why Drupal is complaining, but here we are.
Fixed
8.1
Code
I encounter the same problem and the patch provided fixed the issue. Thanks