div class="container" missing in firefox

That´s exactly what I mean. The content is fullwidth. But this is wrong!! It should NOT be fullwidth. You can see, if you refresh the site or watch on another browser, than it is right.
Best regards,
Kathrin

I use stretched layout, while the header-Slider should be full-width.
How I explained one, the problem does disappear if you refresh the site. And it is, because the <div class=”container”> is absent. If you reload, this div appears!!!

I think you dont understand the problem:
Cant you see, that there is another HTML-code after refreshing the site??? I WANT the webseite running on firefox and chrome!!
If you watch the site the first time HTML looks like this:
<div id=”layer_slider_2″ class=”avia-layerslider main_color avia-shadow container_wrap fullsize” style=”height: auto;”>
<div class=”flex_column av_one_full first “>
<div class=”av-special-heading av-special-heading-h3 meta-heading ” style=”padding-bottom:10px;”>
After refreshing it is like this:
<div id=”layer_slider_1″ class=”avia-layerslider main_color avia-shadow avia-builder-el-0 el_before_av_one_full avia-builder-el-first container_wrap fullsize” style=”height: auto;”>
<div id=”after_layer_slider_1″ class=”main_color container_wrap fullsize”>
<div class=”container”>
<div class=”template-page content twelve alpha units”>
<div class=”post-entry post-entry-type-page post-entry-1302″>
<div class=”entry-content-wrapper clearfix”>
<div class=”flex_column av_one_full first avia-builder-el-1 el_after_av_layerslider el_before_av_one_full avia-builder-el-first “>

WHY does it change after refreshing???

Now I think (I hope) that I fixed the problem. I wrote a additional css für small devices on the begin of the additional css, Now I changed the position to the end of additional css and it seems that the problem isn´t there any more.