Fixed: Trying to add a series when root folders hadn't populated

Fixed #3387

frontend/src/Components/Form/RootFolderSelectInputConnector.js

@@ -95,6 +95,27 @@ class RootFolderSelectInputConnector extends Component {
     }
   }
 
+  componentDidUpdate(prevProps) {
+    const {
+      name,
+      value,
+      values,
+      onChange
+    } = this.props;
+
+    if (prevProps.values === values) {
+      return;
+    }
+
+    if (!value && values.length && values.some((v) => !!v.key && v.key !== ADD_NEW_KEY)) {
+      const defaultValue = values[0];
+
+      if (defaultValue.key !== ADD_NEW_KEY) {
+        onChange({ name, value: defaultValue.key });
+      }
+    }
+  }
+
   //
   // Listeners
 

src/Sonarr.Api.V3/Series/SeriesFolderAsRootFolderValidator.cs

@@ -25,6 +25,9 @@ namespace Sonarr.Api.V3.Series
             if (seriesResource == null) return true;
 
             var rootFolderPath = context.PropertyValue.ToString();
+
+            if (rootFolderPath.IsNullOrWhiteSpace()) return true;
+
             var rootFolder = new DirectoryInfo(rootFolderPath).Name;
             var series = seriesResource.ToModel();
             var seriesFolder = _fileNameBuilder.GetSeriesFolder(series);