How to change the favicon in the default Frontend's theme
The favicon of the default Frontend's theme could be changed in same way like is uploaded the logo. By default there is not a favicon.
I've added even logo selector for the default Frontend Midrub's Theme and you will see this option in the Midrub -> Administrator -> Frontend -> Frontend Settings -> Midrub Theme. With just a click you can add your custom favicon. Ensure the favicon has no more than 50 px width + height because will affect the speed.