fromJS does not maintain order of object properties. Use a reviver function with fromJS inside the response.jsx component for the passed down schema prop.

src/core/components/parameter-row.jsx

@@ -81,7 +81,6 @@ export default class ParameterRow extends Component {
     const Markdown = getComponent("Markdown")
 
     let schema = param.get("schema")
-
     let type = isOAS3 && isOAS3() ? param.getIn(["schema", "type"]) : param.get("type")
     let isFormData = inType === "formData"
     let isFormDataSupported = "FormData" in win

src/core/components/response.jsx

@@ -117,7 +117,7 @@ export default class Response extends React.Component {
             <ModelExample
               getComponent={ getComponent }
               specSelectors={ specSelectors }
-              schema={ fromJS(schema) }
+              schema={ fromJS(schema, (key, value) => value.toOrderedMap() ) }
               example={ example }/>
           ) : null}