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.
step 1:
Notice you should use “Browser direct connection” option
Step 2:
Click on the localhost link
Step 3:
Click on “Advanced” and then “Proceed to localhost (unsafe)”
Step 4:
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.