Make notification rules queryable

core/templates/window-content/search.html

@@ -404,4 +404,9 @@
       value="{{ params.tags }}">
   </div>
   <div class="is-hidden"></div>
+  {% if params.rule is not None %}
+    <div style="display:none;">
+      <input name="rule" value="{{ params.rule }}">
+    </div>
+  {% endif %}
 </form>