if (ImNodes::Ez::BeginNode(node, node->m_var_name, &node->m_pos, &node->m_selected))
{
ImGui::Separator(); //here
//other drawings
}
results to

More testing shows that anywhere the ImGui::Separator() is called as long as inside the ImNodes::Ez::BeginNode and ImNodes::Ez::EndNode it results to the same problem
results to

More testing shows that anywhere the ImGui::Separator() is called as long as inside the
ImNodes::Ez::BeginNodeandImNodes::Ez::EndNodeit results to the same problem