PostLogoutRedirectUri always null in identity Server 4 with Angular OIDC client

Problem

The LogoutId always was NULL in identity Server 4 when the Angular OIDC client redirect to logout.

Remove the post_logout_redirect_uri setting

var config = {
        authority: 'http://localhost:4242/',
        client_id: 'spa-client',
        redirect_uri: `http://localhost:4200/oidc-login-redirect.html`,
        scope: 'openid projects-api profile',
        response_type: 'id_token token',
        //*------REMOVE THIS, OTHERWISE THE LOGOUTID ALWAYS NULL  -------*/
        // post_logout_redirect_uri: `${Constants.clientRoot}`,
        //*------REMOVE THIS, OTHERWISE THE LOGOUTID ALWAYS NULL  -------*/       
    }
   

Please refer the link here