Fix th border on some tables

app/assets/stylesheets/content/_table.sass

@@ -209,7 +209,6 @@ table.generic-table
 
 .generic-table--header-outer,
 .generic-table--sort-header-outer,
-.generic-table--empty-header
   padding:      0 6px
   line-height:  $generic-table--header-height
   z-index:      1
@@ -219,6 +218,12 @@ table.generic-table
   &.hover
     background:   #f8f8f8
 
+.generic-table--empty-header
+  padding:       0 6px
+  height:        calc(#{$generic-table--header-height} + 1px)
+  border-bottom: 1px solid $table-row-border-color
+  z-index:       1
+
 .generic-table--column-spacer
   white-space:  nowrap
   padding:      0 6px

app/cells/views/table/show.erb

@@ -43,6 +43,7 @@ See doc/COPYRIGHT.rdoc for more details.
           <% end %>
           <th>
             <%# last column for buttons %>
+            <div class="generic-table--empty-header"></div>
           </th>
         </tr>
       </thead>