winutil/functions/public/Invoke-WPFSelectedCheckboxesUpdate.ps1

function Invoke-WPFSelectedCheckboxesUpdate ($type, $checkboxName) {
    $listName = switch -Regex ($checkboxName) {
        '^WPFInstall' { 'selectedApps' }
        '^WPFTweaks'  { 'selectedTweaks' }
        '^WPFToggle'  { 'selectedToggles' }
        '^WPFFeature' { 'selectedFeatures' }
        '^WPFAppx'    { 'selectedAppx' }
    }

    $selectionChanged = $false
    if ($type -eq "Add") {
        if (-not $sync.$listName.Contains($checkboxName)) {
            $sync.$listName.Add($checkboxName)
            $selectionChanged = $true
        }
    } else {
        $selectionChanged = $sync.$listName.Remove($checkboxName)
    }

    if ($listName -eq "selectedApps" -and $selectionChanged) {
        $sync.WPFselectedAppsButton.Content = "Selected Apps: $($sync.selectedApps.Count)"
        $sync.selectedAppsstackPanel.Children.Clear()
        $sync.selectedApps | Sort-Object | ForEach-Object {
            Add-SelectedAppsMenuItem -name $sync.configs.applicationsHashtable.$_.Content -key $_
        }
    }
}