GraphXR requires https connection. However, https port on your localhost Neo4j DB instance is probably without certificate. You can accept and still connect to it.
Notice you should use “Browser direct connection” option
Click on the localhost link
Click on “Advanced” and then “Proceed to localhost (unsafe)”
You will see a mostly blank page close this, and go back to project page, click confirm.
You can use this technique to connect to your other Neo4j databases that doesn’t have certificate installed.