Have you previously customized the user_notifications.signup_after_approval.text_body_template?
The default text I’m seeing for this template in the server.en.yml file is:
Welcome to %{site_name}!
A staff member approved your account on %{site_name}.
You can now access your new account by logging in at:
%{base_url}
If the above link is not clickable, try copying and pasting it into the address bar of your web browser.
%{new_user_tips}
We believe in [civilized community behavior](%{base_url}/guidelines) at all times.
Enjoy your stay!
It doesn’t contain an %{email_token} key.