IUIAutomation not working - Windows.Automation does - Get selected text

I converted my System.Windows.Automation code to the newer, faster IUIAutomation framework. I want to get the current selected text in any application (other app needs to support Automation of course). See the NEW Code below:

CUIAutomation _automation = new CUIAutomation();                    
var element = _automation.GetFocusedElement();
                    if (element != null)
                        {
                        IUIAutomationTextPattern textPattern = (IUIAutomationTextPattern) element.GetCurrentPattern(10014);

                        if(textPattern != null)
                        {
                            var sb = new StringBuilder();
                            var range =  textPattern.GetSelection();
                            sb.Append(range.GetElement(0).GetText(-1));
                            return sb.ToString();
                        }
                    }

Weirdly, this code only works in Visual Studio itself and no other app where it should (Edge browser for example), but when I add (add the beginning of the function) the following codepiece from the old System.Windows.Automation framework it suddenly works in expected apps (Edge browser for example).

var x = AutomationElement.FocusedElement;