Some response filter tweaks

app/ui/components/codemirror/code-editor.js

@@ -602,7 +602,7 @@ class CodeEditor extends PureComponent {
         />
       );
 
-      if (filterHistory.length) {
+      if (filterHistory && filterHistory.length) {
         toolbarChildren.push(
           <Dropdown key="history" className="tall" right>
             <DropdownButton className="btn btn--compact">
@@ -709,7 +709,7 @@ CodeEditor.propTypes = {
   defaultTabBehavior: PropTypes.bool,
   readOnly: PropTypes.bool,
   filter: PropTypes.string,
-  filterHistory: PropTypes.arrayOf(PropTypes.string.isRequired).isRequired,
+  filterHistory: PropTypes.arrayOf(PropTypes.string.isRequired),
   singleLine: PropTypes.bool,
   debounceMillis: PropTypes.number,
   dynamicHeight: PropTypes.bool

app/ui/containers/app.js

@@ -382,6 +382,11 @@ class App extends PureComponent {
         return;
       }
 
+      // Blank?
+      if (!responseFilter) {
+        return;
+      }
+
       responseFilterHistory.unshift(responseFilter);
       await this._updateRequestMetaByParentId(requestId, {responseFilterHistory});
     }, 2000);