chore(chart): Save modal select placeholder value (#12413)

* Fix SaveModal select value

* var name change and null

* Address Comments

superset-frontend/src/explore/components/SaveModal.tsx

@@ -158,6 +158,11 @@ class SaveModal extends React.Component<SaveModalProps, SaveModalState> {
  }
 
  render() {
+ const dashboardSelectValue =
+ this.state.saveToDashboardId || this.state.newDashboardName;
+ const valueObj = dashboardSelectValue
+ ? { value: dashboardSelectValue }
+ : null;
  return (
  <StyledModal
  show
@@ -248,15 +253,13 @@ class SaveModal extends React.Component<SaveModalProps, SaveModalState> {
  <CreatableSelect
  id="dashboard-creatable-select"
  className="save-modal-selector"
+ menuPosition="fixed"
  options={this.props.dashboards}
  clearable
  creatable
  onChange={this.onDashboardSelectChange}
  autoSize={false}
- value={{
- value:
- this.state.saveToDashboardId || this.state.newDashboardName,
- }}
+ value={valueObj}
  placeholder={
  // Using markdown to allow for good i18n
  <ReactMarkdown