src/vs/platform/windows/electron-main/windowImpl.ts/CodeWindow/isFullScreen
class CodeWindow:	get isFullScreen(): boolean {
		if (isMacintosh && typeof this.transientIsNativeFullScreen === 'boolean') {
			return this.transientIsNativeFullScreen;
		}

		return this._win.isFullScreen() || this._win.isSimpleFullScreen();
	}