No problem Jane.
Not sure why the color for the menu toggle has changed to white as the option should not affect it. I'll take a look at the plugin in more details as I continue working on its update due out soon.
In the meantime as a workaround, Could I ask you to add the following CSS code via a custom CSS plugin to resolve the issue...
.menu-toggle:before {
color: #062F63;
}The above color would match your header/logo color but you can change it to any color of your choice.
Regards,
Zulf