diff --git a/brozzler/js-templates/umbraBehavior.js.j2 b/brozzler/js-templates/umbraBehavior.js.j2
index 24f268d..278c956 100644
--- a/brozzler/js-templates/umbraBehavior.js.j2
+++ b/brozzler/js-templates/umbraBehavior.js.j2
@@ -25,7 +25,7 @@ class UmbraBehavior {
         this.alreadyDone = [];
         this.idleSince = null;
         this.intervalId = null;
-        this.intervalTimeMs = {{interval or '300'}};
+        this.intervalTimeMs = {{interval or 300}};
         this.index = 0;
     }
 
@@ -33,7 +33,8 @@ class UmbraBehavior {
         // should match older default and simpleclicks behavior, and more
         var k = this.index;
         var selector = this.actions[k].selector;
-        var skipIDCheck = this.actions[k].skipIDcheck ? this.actions[k].skipIDcheck !== false : false;
+        var skipIDCheck = this.actions[k].skipIDcheck ? this.actions[k].skipIDcheck != false : false;
+        var onceOnly = this.actions[k].onceOnly ? this.actions[k].onceOnly != false: false;
         var action = this.actions[k].do ? this.actions[k].do : 'click';
         var closeSelector = this.actions[k].closeSelector ? this.actions[k].closeSelector : null;
         var didSomething = false;
@@ -57,7 +58,11 @@ class UmbraBehavior {
                     doTarget(closeTargets[0], 'click');
                 }
             }
-            var doTargets = documents[j].querySelectorAll(selector);
+            if (onceOnly) {
+                var doTargets = [ documents[j].querySelector(selector) ];
+            } else {
+                var doTargets = documents[j].querySelectorAll(selector);
+            }
             var doTargetsLength = doTargets.length;
             if (!(doTargetsLength > 0)) {
                 continue;