diff --git a/API/Backend/Config/validate.js b/API/Backend/Config/validate.js
index e6cd9b24..d1d11ffd 100644
--- a/API/Backend/Config/validate.js
+++ b/API/Backend/Config/validate.js
@@ -39,6 +39,7 @@ const validateStructure = (config) => {
 const validateLayers = (config) => {
   let errs = [];
 
+  let existingUUIDs = [];
   Utils.traverseLayers(config.layers, (layer) => {
     // Check layer name
     const validNameErrs = isValidLayerName(layer.name);
@@ -90,9 +91,17 @@ const validateLayers = (config) => {
           err(`Unknown layer type: '${layer.type}'`, ["layers[layer].type"])
         );
     }
-  });
 
-  errs = errs.concat(hasNonHeaderWithSublayers(config));
+    if (layer.uuid != null) {
+      if (existingUUIDs.includes(layer.uuid)) {
+        errs = errs.concat([
+          err(
+            `Found a layer with duplicate uuid: ${layer.name} - ${layer.uuid}`
+          ),
+        ]);
+      } else existingUUIDs.push(layer.uuid);
+    }
+  });
 
   return errs;
 };
diff --git a/config/js/config.js b/config/js/config.js
index c9935f93..e1adfc16 100644
--- a/config/js/config.js
+++ b/config/js/config.js
@@ -1954,10 +1954,9 @@ function mmgisLinkModalsToLayersCloneClick(e) {
   var mainThis = $(this).parent().parent().parent().parent();
   var mainId = mainThis.attr("id");
   mainId = mainId.substring(mainId.indexOf("_") + 1);
-  makeLayerBarAndModal(
-    dataOfLastUsedLayerSlot[mainId],
-    dataOfLastUsedLayerSlot[mainId].__level
-  );
+  const cloned = JSON.parse(JSON.stringify(dataOfLastUsedLayerSlot[mainId]));
+  delete cloned.uuid;
+  makeLayerBarAndModal(cloned, cloned.__level);
 
   refresh();
 }