diff --git a/packages/node_modules/@node-red/editor-client/src/js/nodes.js b/packages/node_modules/@node-red/editor-client/src/js/nodes.js
index 62949efce..63027aed1 100644
--- a/packages/node_modules/@node-red/editor-client/src/js/nodes.js
+++ b/packages/node_modules/@node-red/editor-client/src/js/nodes.js
@@ -17,6 +17,8 @@ RED.nodes = (function() {
 
     var node_defs = {};
     var nodes = [];
+    var nodeTabMap = {};
+
     var configNodes = {};
     var links = [];
     var defaultWorkspace;
@@ -213,6 +215,11 @@ RED.nodes = (function() {
                 n.i = nextId+1;
             }
             nodes.push(n);
+            if (nodeTabMap[n.z]) {
+                nodeTabMap[n.z][n.id] = n;
+            } else {
+                console.warn("Node added to unknown tab/subflow:",n);
+            }
         }
         RED.events.emit('nodes:add',n);
     }
@@ -246,6 +253,9 @@ RED.nodes = (function() {
             node = getNode(id);
             if (node) {
                 nodes.splice(nodes.indexOf(node),1);
+                if (nodeTabMap[node.z]) {
+                    delete nodeTabMap[node.z][node.id];
+                }
                 removedLinks = links.filter(function(l) { return (l.source === node) || (l.target === node); });
                 removedLinks.forEach(function(l) {links.splice(links.indexOf(l), 1); });
                 var updatedConfigNode = false;
@@ -300,6 +310,8 @@ RED.nodes = (function() {
 
     function addWorkspace(ws,targetIndex) {
         workspaces[ws.id] = ws;
+        nodeTabMap[ws.id] = {};
+
         ws._def = RED.nodes.getType('tab');
         if (targetIndex === undefined) {
             workspacesOrder.push(ws.id);
@@ -312,6 +324,7 @@ RED.nodes = (function() {
     }
     function removeWorkspace(id) {
         delete workspaces[id];
+        delete nodeTabMap[ws.id];
         workspacesOrder.splice(workspacesOrder.indexOf(id),1);
 
         var removedNodes = [];
@@ -357,6 +370,8 @@ RED.nodes = (function() {
             sf.name = subflowName;
         }
         subflows[sf.id] = sf;
+        nodeTabMap[sf.id] = {};
+
         RED.nodes.registerType("subflow:"+sf.id, {
             defaults:{
                 name:{value:""},
@@ -393,6 +408,7 @@ RED.nodes = (function() {
     }
     function removeSubflow(sf) {
         delete subflows[sf.id];
+        delete nodeTabMap[sf.id];
         registry.removeNodeType("subflow:"+sf.id);
     }
 
@@ -1266,12 +1282,13 @@ RED.nodes = (function() {
     // TODO: supports filter.z|type
     function filterNodes(filter) {
         var result = [];
+        var searchSet = nodes;
+        if (filter.hasOwnProperty("z") && Object.hasOwnProperty("values") && nodeTabMap.hasOwnProperty(filter.z) ) {
+            searchSet = Object.values(nodeTabMap[filter.z]);
+        }
 
-        for (var n=0;n<nodes.length;n++) {
-            var node = nodes[n];
-            if (filter.hasOwnProperty("z") && node.z !== filter.z) {
-                continue;
-            }
+        for (var n=0;n<searchSet.length;n++) {
+            var node = searchSet[n];
             if (filter.hasOwnProperty("type") && node.type !== filter.type) {
                 continue;
             }
@@ -1339,6 +1356,7 @@ RED.nodes = (function() {
     function clear() {
         nodes = [];
         links = [];
+        nodeTabMap = {};
         configNodes = {};
         workspacesOrder = [];
         var subflowIds = Object.keys(subflows);