SendKeys Command, Page_Down does not work

Hi, I am trying to execute the following command in a test case;
WebUI.sendKeys(findTestObject(null), Keys.chord(Keys.COMMAND, Keys.PAGE_DOWN)

I can get this to work as a simple Keys.PAGE_DOWN, but when I try to use Command + Page_Down (or Control + Page_Down, etc) the web page does nothing.

Below is the entire test case (including import org.openqa.selenium.Keys as Keys);

import static com.kms.katalon.core.testcase.TestCaseFactory.findTestCase
import static com.kms.katalon.core.testdata.TestDataFactory.findTestData
import static com.kms.katalon.core.testobject.ObjectRepository.findTestObject
import com.kms.katalon.core.checkpoint.Checkpoint as Checkpoint
import com.kms.katalon.core.cucumber.keyword.CucumberBuiltinKeywords as CucumberKW
import as Mobile
import com.kms.katalon.core.model.FailureHandling as FailureHandling
import com.kms.katalon.core.testcase.TestCase as TestCase
import com.kms.katalon.core.testdata.TestData as TestData
import com.kms.katalon.core.testobject.TestObject as TestObject
import com.kms.katalon.core.webservice.keyword.WSBuiltInKeywords as WS
import com.kms.katalon.core.webui.keyword.WebUiBuiltInKeywords as WebUI
import internal.GlobalVariable as GlobalVariable
import org.openqa.selenium.Keys as Keys




WebUI.setText(findTestObject('Synzi Admin/Synzi EA Staff Create OR/input_username_username'), 'qa-automation')


WebUI.setText(findTestObject('Synzi Admin/SynziAdmin Login OR/input_Password_password'), GlobalVariable.qaAutomationPassword)


'Sign in to App as Synzi Amin''Synzi Admin/SynziAdmin Login OR/button_Sign In'))


String SynziAdmin = 'QA Automation'

String adminPermission = 'Administrator'

'1555535285 or 1555945359'
String tempDisplayName = 'QA SynziAdmin_1555945359'

'789-3) Click on Synzi Accounts in left sidebar''Synzi Admin/a_Synzi Accounts'))


'Click on item in list, to establish place to Command + Page_Down''Synzi Admin/Page_Synzi Admin/div_QA SynziAdmin_List_Disabled_User'), FailureHandling.CONTINUE_ON_FAILURE)


'Command + Page_Down to scroll to bottom of long list'
WebUI.sendKeys(findTestObject(null), Keys.chord(Keys.COMMAND, Keys.PAGE_DOWN))

I think you must specify the element, which you send keys on. I’d choose any visible element on the page.

When I just send like this, it works (the reason for the WebUI click above it is to “set” a place in the web page to perform the Page Down);
WebUI.sendKeys(findTestObject(null), Keys.chord(Keys.PAGE_DOWN))

When I say works, it does page down, if I could get the web page to Command + Page_Down, my test would work.