when using antd-mobile, I found that the Modal mask flashes when the mask component fades in and out. 
 later, when I used chrome"s animation to view the animation, I found that the animation of the mask layer was executed twice, that is, the first white = "gray =" gray, while the normal one is white = "gray; 
  
as shown in the figure above, the first is a situation where there is no problem; the second is a situation where there is a problem
the code is as follows:
  <div className="submit-wrapper">
    <Button type="primary" onClick={this.handleRegister}>
      
    </Button>
  </div>  handleRegister = () => {
    Modal.alert("", "", [
      {
        text: ""
      }
    ]);
    // }
  };what causes the animation to be executed twice?
