<%= form_for(ActivityNotification::Subscription.new, as: :subscription, url: subscriptions_url_for(target, option_params), data: { remote: true }) do |f| %>
<%= f.hidden_field :key, value: key %>
<%= key %>
<%= link_to "Notifications", notifications_path_for(target, option_params.merge(filtered_by_key: key)) %>
<% target.notifications.filtered_by_key(key).latest.optional_target_names.each do |optional_target_name| %>
<% end %>
<% end %>