diff --git a/src/js/hnswitches.js b/src/js/hnswitches.js
index 1ae3de10c..cd1317773 100644
--- a/src/js/hnswitches.js
+++ b/src/js/hnswitches.js
@@ -104,6 +104,7 @@ HnSwitches.toBroaderHostname = toBroaderHostname;
 
 HnSwitches.prototype.reset = function() {
     this.switches = {};
+    this.z = '';
 };
 
 /******************************************************************************/
@@ -229,6 +230,7 @@ HnSwitches.prototype.evaluateZ = function(switchName, hostname) {
         if ( bits !== 0 ) {
             bits = bits >> bitOffset & 3;
             if ( bits !== 0 ) {
+                this.z = s;
                 return bits === 1;
             }
         }
diff --git a/src/js/tab.js b/src/js/tab.js
index ef44a3334..c84f6faf6 100644
--- a/src/js/tab.js
+++ b/src/js/tab.js
@@ -452,7 +452,7 @@ vAPI.tabs.onPopup = function(details) {
 
     // Check user switch first
     if ( µb.hnSwitches.evaluateZ('no-popups', openerHostname) ) {
-        result = 'ub:no-popups true';
+        result = 'ub:no-popups: ' + µb.hnSwitches.z + ' true';
     }
 
     // https://github.com/chrisaljoudi/uBlock/issues/323
diff --git a/src/js/traffic.js b/src/js/traffic.js
index 6530eb921..666122529 100644
--- a/src/js/traffic.js
+++ b/src/js/traffic.js
@@ -161,7 +161,7 @@ var onBeforeRootFrameRequest = function(details) {
 
     // Permanently unrestricted?
     if ( result === '' && µb.hnSwitches.evaluateZ('no-strict-blocking', requestHostname) ) {
-        result = 'ua:no-strict-blocking on';
+        result = 'ua:no-strict-blocking: ' + µb.hnSwitches.z + ' true';
     }
 
     // Temporarily whitelisted?