The Challenge for this (https://developer.salesforce.com/en/trailhead/force_com_programmatic_beginner/visualforce_fundamentals/visualforce_variables_expressions)Trailhead unit asks us to create a VisualForce page named "myHelloWorldVF" that displays the first name of the logged-in user.

Here is the VF I am using:

<apex:page>
{!$User.FirstName}
</apex:page>

(note: I have also tried wrapping the binding inside tags like <div>, <p>, <apex:outputText>, etc with no luck. I also tried minimizing the rendered output by including sidebar="false" standardStylesheets="false" showHeader="false")

The error returned in Trailhead after clicking "Check Challenge" is:
I am not aware of a different global var within VF for getting User attributes.

Anyone have luck with getting this one to pass?