I just noticed the same thing with the function "Icon type". There it jumps back again and again to "Dashicons" after saving.
And how can I use "$prefix" in the "MB Builder" plugin?
I also have an extra settings page and WPML in use. I created it with the Page Builder. How can I translate the fields now?
Settings page https://abload.de/img/bildschirmfoto2018-12qxfh0.png
Code in the template https://abload.de/img/bildschirmfoto2018-12w3fdw.png
Result on the front page https://abload.de/img/bildschirmfoto2018-1277etz.png