its good!

will it be merge？ its looks cool

will it be merge?

It isn't finished yet and not even ready for review

Now I don't see any bugs, but probably not every case is handled or some of them handled incorrectly.
I think PR is mostly ready. I'll check how I want to use it with fancy_title_bar = false, maybe it's better to just hide the native buttons in that case.

RTL is handled:

For testing I enabled rtl using the following code inside of the app:

// somewhere in window/src/os/macos/window.rs
 unsafe {
    let user_defaults = <id as cocoa::foundation::NSUserDefaults>::standardUserDefaults();

    cocoa::foundation::NSUserDefaults::setBool_forKey_(
        user_defaults,
        YES,
        *nsstring("AppleTextDirection"),
    );
    cocoa::foundation::NSUserDefaults::setBool_forKey_(
        user_defaults,
        YES,
        *nsstring("NSForceRightToLeftWritingDirection"),
    );
}

(applies after restart, call with NO to disable).