window.SetUserAgent() dose not work on linux

[towerbit]

The method 'SetUserAgent' works well on windows, but it never changes the user-agent on linux such as Debian 12.4 which always return 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Safari/605.1.15')' by javascript navigator.userAgent.

I tried to set user-agent at first, it seems changed but make no sense to navigator.userAgent.
var window = new PhotinoWindow(); window.UserAgent="Custom user agent"; Console.WriteLine(window.UserAgent);