Resolved
Resolved in: Toolset Customizr Integration 1.6
The problem happens when you see a page /sample-page/ with mobile size, the problem occurs with whatever browser: when dropdown menu opens it immediately closes (it open and closes altogether and all of a sudden).
The theme should be updated to latest version, and this CSS rules should be added to your style.css file
#wpadminbar{
position: fixed !important;
}
.nav-collapse.tc-hover-menu-wrapper.collapse.in{
height: auto !important;
}