app/views/users/mailer/invitation_instructions.text.erb
<%= t("devise.mailer.invitation_instructions.hello", email: @resource.email) %>
<%= t("devise.mailer.invitation_instructions.someone_invited_you", name: @resource.invited_by&.name, url: root_url) %>
<%= accept_invitation_url(@resource, :invitation_token => @token) %>
<% if @resource.invitation_due_at %>
<%= t("devise.mailer.invitation_instructions.accept_until", due_date: @resource.invitation_due_at.strftime('%A %B %d, %Y at %I:%M %p')) %>
<% end %>
<%= strip_tags t("devise.mailer.invitation_instructions.ignore") %>