I tried using React.FormEvent<HTMLSelectElement> but it led to an error in the editor, even though there is no EventTarget visible in the code:
The property ‘value’ does not exist on value of type ‘EventTarget’
Then I changed React.FormEvent to React.ChangeEvent and it helped:
private changeName(event: React.ChangeEvent<HTMLSelectElement>) {
event.preventDefault();
this.props.actions.changeName(event.target.value);
}