openproject/app/views/mailer/_notification_row.html.erb

<a style="border: 1px solid #E0E0E0;
  margin-bottom: 16px;
  padding: 12px 12px 16px 12px;
  border-radius: 10px;
  text-decoration: none;
  display: block;"
   href="<%= notifications_path(work_package.id) %>"
   target="_blank">
  <table width="100%" border="0" cellpadding="0" cellspacing="0" style="margin-bottom: 9px; font-size: 14px;">
    <tr>
      <td >
        <div style="color: #333333;
                    background-color: #FFFFFF;
                    <%= status_colors(work_package.status) %>
                    white-space: nowrap;
                    padding: 2px 12px;
                    height: 16px;">
          <%= work_package.status %>
        </div>
      </td>
      <td width="100%" style="padding-left: 8px;
                              color: #878787;">

        #<%= work_package.id %> - <%= work_package.project %>
        <% unique_reasons = unique_reasons_of_notifications(notifications_by_work_package) %>
        <%=  ' - ' unless unique_reasons.length === 1 && unique_reasons.first.nil? %>
        <% unique_reasons.each_with_index do |reason, index| %>
          <%= I18n.t(
                :"mail.digests.work_packages.reason.#{reason || :unknown}",
                default: '') %><%= ', ' unless unique_reasons.size-1 == index  %>
        <% end %>
      </td>
      <td style="text-align: right;">
          <span style="background-color: #00A3FF;
            color: white;
            border-radius: 8px;
            padding: 0px 8px;
            font-size: 14px;">
           <%= notifications_by_work_package.length %>
          </span>
      </td>
    </tr>
  </table>
  <table width="100%" border="0" cellpadding="0" cellspacing="0" style="margin-bottom: 9px; font-size: 16px; font-weight: bold;">
    <tr>
      <td style="color: <%= type_color(work_package.type, '#333333') %>;
                 white-space: nowrap;">
        <%= work_package.type.to_s.upcase %>
      </td>
      <td width="100%" style="padding-left: 5px; color: #333333;">
        <%= work_package.subject %>
      </td>
    </tr>
  </table>

  <%= yield %>
</a>