Html.w-mod-touch & firefox

I’m using a fixed position image inside a section. All works well except in Mac Firefox 59.0.1. The image scrolls on desktop and is controlled by this rule in the webflow css:
*html.w-mod-touch * {
background-attachment: scroll !important;

Do I need to go into the webflow.css and set this rule to be mobile only? Not sure why it’s not. Thoughts?

Here is my site Read-Only: LINK
(how to share your site Read-Only link)

For a temp workaround I added “!important” to the css rules.

For instance, the webflow generated rule for the background classes
are “background-attachment: scroll, fixed”

I edited to "background-attachment: scroll, fixed !important; "
and the issue in Firefox was resolved.

Hoping this does not effect other conditions or browsers.