Googel api local ip does not work

trying to install node-red-contrib-google-oauth2 but when I have to fill in the information according to the page

"Choose Web Application.
As Authorized JavaScript origins enter your Node-RED IP (e.g. http: // localhost: 1880)
As Authorized redirect URIs enter your Node-RED IP plus / google-credentials / auth / callback (e.g. http: // localhost: 1880 / google-credentials / auth / callback)

so everything works except on the last point As Authorized redirect URIs as soon as I try to write; 1880 ......

says it "Invalid Redirect: must end with a public top-level domain (such as .com or .org)."

how to fill this in?