Do not display spaces bar if it is useless

matrixgw_frontend/src/widgets/messages/SpaceSelector.tsx

@@ -16,6 +16,9 @@ export function SpaceSelector(p: {
     [p.rooms]
   );
 
+  // Do not display space bar if your is not member of any space
+  if (spaces.length === 0) return <></>;
+
   return (
     <div style={{ display: "flex", flexDirection: "column" }}>
       <SpaceButton