Hey Lazer,
The button doesn't have an EasyDiscuss setting. It seems to be generated by your template and I`m not sure why in the first place. Perhaps you can consult your template provider about this. You can hide this button by applying the css code below in your custom css file and recompile your css.
#ed .ed-navbar .btn.btn-sm.btn-default.ed-navbar-submenu-toggle {
display:none !important;
}