https://learn.microsoft.com/zh-cn/dotnet/api/system.windows.automation.textpattern.fontsizeattribute?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
TextPattern.FontSizeAttribute Field (System.Windows.Automation) | Microsoft Learn
Identifies the FontSize attribute of a text range.
field systemtextpatternwindowsautomationmicrosoft