I've looked through the menu under System in Winbox and don't see a way to identify which version of Winbox this is. Is this version info somewhere? The creation date of winbox64.exe is 19 Feb 2024.
It's in the title bar of the first/login window that appears after launch. Once connect, I'm not sure where you could find out winbox version, since the titlebar will show the connected router's version AFTER login.