OK, the off-canvas positioning issue is also a CSS conflict with your Bootstrap CSS.
You are loading this CSS via bootstrap.min.cc
.modal {
bottom: 0;
display: none;
left: 0;
outline: 0 none;
overflow: hidden;
position: fixed;
right: 0;
top: 0;
z-index: 1050;
}
We also have a .modal class that loads in our hosting provider’s must-use plugins CSS. Specifically, the left:0; and bottom:0; declarations are causing the modal to display in the wrong position.
/wp-content/mu-plugins/wpengine-common/css/wpe-common.css
.modal {
background-clip: padding-box;
background-color: #ffffff;
border: 1px solid rgba(0, 0, 0, 0.3);
border-radius: 6px;
box-shadow: 0 3px 7px rgba(0, 0, 0, 0.3);
left: 50%;
margin-left: -280px;
outline: medium none;
position: fixed;
top: 10%;
width: 560px;
z-index: 1050;
}
Since this is in the wp-admin the above jQuery solution won’t work unless you also add it to the <body> tag of the mdocs admin screens, though a custom CSS over-ride won’t work here either because custom CSS is not applied to wp-admin screens.