diff --git a/uhepp-js/src/components/UheppHist.jsx b/uhepp-js/src/components/UheppHist.jsx
index ca5a8238fecea5653a3bf576b0b270263bb0744c..73b66457dbe0db3704e96b21d42c969c48b699f3 100644
--- a/uhepp-js/src/components/UheppHist.jsx
+++ b/uhepp-js/src/components/UheppHist.jsx
@@ -521,9 +521,8 @@ const Legend = ({
   const lineSkip = -16;
   const mathSkip = 120;
   let i = 0
-  let legend = []
-  post_uhepp.graphs.map((graph, graph_i) => {
-
+  let legend = [];
+  (post_uhepp.graphs || []).forEach((graph, graph_i) => {
     legend.push(<>
       <line x1={0} x2={20}
         y1={(i + 1) * lineSkip - 5}
diff --git a/uhepp-js/src/components/UheppHistUI.jsx b/uhepp-js/src/components/UheppHistUI.jsx
index 958f991b0f1b68a1bc8f33591738490a2d610582..c4b8294016dcdba0bbd13ffe569c94c562908887 100644
--- a/uhepp-js/src/components/UheppHistUI.jsx
+++ b/uhepp-js/src/components/UheppHistUI.jsx
@@ -111,10 +111,10 @@ const UheppHistUIWithSyst = ({
       })})
 
   return <>
-		<div>{ Object.entries(uhepp.metadata.tags).map(([key,  value]) => 
+		<div>{ Object.entries(uhepp.metadata.tags).map(([key,  value], i) => 
 				value == null ?
-				<span className="badge badge-pill badge-primary mx-1">{key}</span> :
-				<span className="badge-pair mx-1">
+				<span key={i} className="badge badge-pill badge-primary mx-1">{key}</span> :
+				<span key={i} className="badge-pair mx-1">
 					<span className="badge badge-pill badge-primary">{key}</span>
 					<span className="badge badge-pill badge-secondary">{value}</span>
 				</span>
@@ -156,10 +156,10 @@ const UheppHistUIWithSyst = ({
 					<dd>{ uhepp.metadata.Ecm_TeV ?
 								uhepp.metadata.Ecm_TeV + " TeV" : <i>None</i>}</dd>
 					<dt>Tags</dt>
-					<dd>{ Object.entries(uhepp.metadata.tags).map(([key,  value]) => 
+					<dd>{ Object.entries(uhepp.metadata.tags).map(([key,  value], i) => 
 							value == null ?
-							<span className="badge badge-pill badge-primary mx-1">{key}</span> :
-							<span className="badge-pair mx-1">
+							<span key={i} className="badge badge-pill badge-primary mx-1">{key}</span> :
+							<span key={i} className="badge-pair mx-1">
 								<span className="badge badge-pill badge-primary">{key}</span>
 								<span className="badge badge-pill badge-secondary">{value}</span>
 							</span>
@@ -222,7 +222,7 @@ const UheppHistUIWithSyst = ({
 						<label htmlFor="envelop">Add envelop of </label>
 						<select value={envName} className="form-control" id="envelop" onChange={(e) => onEnvChange(e)}>
               { [
-                <option value="NOMINAL" key="-1">Nominal</option>,
+                <option value="NOMINAL" key={"nonminal"}>Nominal</option>,
                 ...variations.map((name, i) => <option value={name} key={i}>{name}</option>)
                 ]
               }