Hummingbird interferes with Divi Custom CSS field

Hi Gurus,

I finally ported my development site over to my live site and things seemed good. So i activated all the Hummingbird stuff. What I've noticed is that some of the Custom CSS I entered through the Theme Custom CSS field is no longer working.

Its as though the Custom CSS isn't there. However the correct code is in the field. I'm wondering if you can take a look and give me some ideas about how Hummingbird might be affecting the Custom CSS?
For example, prior to minification, the following Custom CSS worked perfectly:
.et_pb_slider .et_pb_slide {box-shadow: none;}
#mp-products-list-widget a.button:focus, button.mp_button:hover, button.mp_button:focus {
background-color: #87d600;}

Now they don't. I'm not exactly sure how to track down where in the flow, Custom CSS is being handled...

Its a long shot I know. Whatever you can suggest I'm all ears.