mastodon/app/views/user_mailer/confirmation_instructions.en.html.erb

<p>Welcome <%= @resource.email %> !</p>

<p>You just created an account on <%= @instance %>.</p>

<p>To confirm your inscription, please click on the following link : <br>
<%= link_to 'Confirm my account', confirmation_url(@resource, confirmation_token: @token) %>

<p>Please also check out our <%= link_to 'terms and conditions', terms_url %>.</p>

<p>Sincerely,<p>

<p>The <%= @instance %> team</p>