@media (min-width: 1200px) {
.container {
width: 1200px;
}
}is in /wp-content/themes/global-disciples-child-theme/style.css on line 86.
The Trusted Pro theme also defines the container width as 1160px by default (this can be changed in the customizer settings though) so I’m not really sure why it is needed in the child theme too.
But in any case, the container element should not be used in the text area of each featured service as it is designed to set the width of the header, page content and footer container centered within the overall full-width view.
I think the main issue is the slider plugin is possibly set to display the slides in a horizontal carousel format rather than each slide sliding into/over the previous slide, so forcing the whole of the homepage to be a lot wider than it should. It’s not only Firefox, it is also the same in Chrome etc.
See the blue highlighted code in the screenshot below which shows how the overall width of the slider is 13321 pixels wide.
