diff --git a/src/constants.ts b/src/constants.ts
index 8c6bc544e0..12e65d401d 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -62,6 +62,8 @@ export const COURSE_BLOCK_NAMES = ({
   libraryContent: { id: 'library_content', name: 'Library content' },
   splitTest: { id: 'split_test', name: 'Split Test' },
   component: { id: 'component', name: 'Component' },
+  itembank: { id: 'itembank', name: 'Problem Bank' },
+  legacyLibraryContent: { id: 'library_content', name: 'Randomized Content Block' },
 });
 
 export const STUDIO_CLIPBOARD_CHANNEL = 'studio_clipboard_channel';
diff --git a/src/course-unit/CourseUnit.jsx b/src/course-unit/CourseUnit.jsx
index 10a9ad25b0..ee03c1bd09 100644
--- a/src/course-unit/CourseUnit.jsx
+++ b/src/course-unit/CourseUnit.jsx
@@ -50,6 +50,7 @@ const CourseUnit = ({ courseId }) => {
     isUnitVerticalType,
     isUnitLibraryType,
     isSplitTestType,
+    isProblemBankType,
     staticFileNotices,
     currentlyVisibleToStudents,
     unitXBlockActions,
@@ -219,6 +220,7 @@ const CourseUnit = ({ courseId }) => {
                   parentLocator={blockId}
                   isSplitTestType={isSplitTestType}
                   isUnitVerticalType={isUnitVerticalType}
+                  isProblemBankType={isProblemBankType}
                   handleCreateNewCourseXBlock={handleCreateNewCourseXBlock}
                   addComponentTemplateData={addComponentTemplateData}
                 />
diff --git a/src/course-unit/add-component/AddComponent.test.jsx b/src/course-unit/add-component/AddComponent.test.tsx
similarity index 99%
rename from src/course-unit/add-component/AddComponent.test.jsx
rename to src/course-unit/add-component/AddComponent.test.tsx
index fafffb0bb8..a9c55b9056 100644
--- a/src/course-unit/add-component/AddComponent.test.jsx
+++ b/src/course-unit/add-component/AddComponent.test.tsx
@@ -14,7 +14,7 @@ import { fetchCourseSectionVerticalData } from '../data/thunk';
 import { getCourseSectionVerticalApiUrl } from '../data/api';
 import { courseSectionVerticalMock } from '../__mocks__';
 import { COMPONENT_TYPES } from '../../generic/block-type-utils/constants';
-import AddComponent from './AddComponent';
+import AddComponent, { AddComponentProps } from './AddComponent';
 import messages from './messages';
 import { IframeProvider } from '../../generic/hooks/context/iFrameContext';
 import { messageTypes } from '../constants';
@@ -56,13 +56,11 @@ jest.mock('../../generic/hooks/context/hooks', () => ({
   }),
 }));
 
-const renderComponent = (props) => render(
+const renderComponent = (props?: AddComponentProps) => render(
   <IframeProvider>
     <AddComponent
-      blockId={blockId}
       isUnitVerticalType
       parentLocator={blockId}
-      addComponentTemplateData={{}}
       handleCreateNewCourseXBlock={handleCreateNewCourseXBlockMock}
       {...props}
     />
@@ -94,7 +92,7 @@ describe('<AddComponent />', () => {
         ),
       });
       expect(btn).toBeInTheDocument();
-      if (component.beta) {
+      if (componentTemplates[component].beta) {
         expect(within(btn).queryByText('Beta')).toBeInTheDocument();
       }
     });
diff --git a/src/course-unit/add-component/AddComponent.jsx b/src/course-unit/add-component/AddComponent.tsx
similarity index 86%
rename from src/course-unit/add-component/AddComponent.jsx
rename to src/course-unit/add-component/AddComponent.tsx
index e0770515ea..17695fb938 100644
--- a/src/course-unit/add-component/AddComponent.jsx
+++ b/src/course-unit/add-component/AddComponent.tsx
@@ -1,5 +1,4 @@
 import { useCallback, useState } from 'react';
-import PropTypes from 'prop-types';
 import { useDispatch, useSelector } from 'react-redux';
 import { getConfig } from '@edx/frontend-platform';
 import { useIntl, FormattedMessage } from '@edx/frontend-platform/i18n';
@@ -21,14 +20,50 @@ import { useEventListener } from '../../generic/hooks';
 import VideoSelectorPage from '../../editors/VideoSelectorPage';
 import EditorPage from '../../editors/EditorPage';
 import { fetchCourseSectionVerticalData } from '../data/thunk';
+import { SelectedComponent } from '../../library-authoring';
+
+type ComponentTemplateData = {
+  displayName: string,
+  category?: string,
+  type: string,
+  beta?: boolean,
+  templates: Array<{
+    boilerplateName?: string,
+    category?: string,
+    displayName: string,
+    supportLevel?: string | boolean,
+  }>,
+  supportLegend: {
+    allowUnsupportedXblocks?: boolean,
+    documentationLabel?: string,
+    showLegend?: boolean,
+  },
+};
+
+export interface AddComponentProps {
+  isSplitTestType?: boolean,
+  isUnitVerticalType?: boolean,
+  parentLocator: string,
+  handleCreateNewCourseXBlock: (
+    args: object,
+    callback?: (args: { courseKey: string, locator: string }) => void
+  ) => void,
+  isProblemBankType?: boolean,
+  addComponentTemplateData?: {
+    blockId: string,
+    parentLocator?: string,
+    model: ComponentTemplateData,
+  },
+}
 
 const AddComponent = ({
   parentLocator,
   isSplitTestType,
   isUnitVerticalType,
+  isProblemBankType,
   addComponentTemplateData,
   handleCreateNewCourseXBlock,
-}) => {
+}: AddComponentProps) => {
   const intl = useIntl();
   const dispatch = useDispatch();
 
@@ -36,16 +71,16 @@ const AddComponent = ({
   const [isOpenHtml, openHtml, closeHtml] = useToggle(false);
   const [isOpenOpenAssessment, openOpenAssessment, closeOpenAssessment] = useToggle(false);
   const { componentTemplates = {} } = useSelector(getCourseSectionVertical);
-  const blockId = addComponentTemplateData.parentLocator || parentLocator;
+  const blockId = addComponentTemplateData?.parentLocator || parentLocator;
   const [isAddLibraryContentModalOpen, showAddLibraryContentModal, closeAddLibraryContentModal] = useToggle();
   const [isVideoSelectorModalOpen, showVideoSelectorModal, closeVideoSelectorModal] = useToggle();
   const [isXBlockEditorModalOpen, showXBlockEditorModal, closeXBlockEditorModal] = useToggle();
 
-  const [blockType, setBlockType] = useState(null);
-  const [courseId, setCourseId] = useState(null);
-  const [newBlockId, setNewBlockId] = useState(null);
+  const [blockType, setBlockType] = useState<string | null>(null);
+  const [courseId, setCourseId] = useState<string | null>(null);
+  const [newBlockId, setNewBlockId] = useState<string | null>(null);
   const [isSelectLibraryContentModalOpen, showSelectLibraryContentModal, closeSelectLibraryContentModal] = useToggle();
-  const [selectedComponents, setSelectedComponents] = useState([]);
+  const [selectedComponents, setSelectedComponents] = useState<SelectedComponent[]>([]);
   const [usageId, setUsageId] = useState(null);
   const { sendMessageToIframe } = useIframe();
   const { useVideoGalleryFlow } = useWaffleFlags(courseId ?? undefined);
@@ -84,7 +119,7 @@ const AddComponent = ({
     dispatch(fetchCourseSectionVerticalData(blockId, sequenceId));
   }, [closeXBlockEditorModal, closeVideoSelectorModal, sendMessageToIframe, blockId, sequenceId]);
 
-  const handleLibraryV2Selection = useCallback((selection) => {
+  const handleLibraryV2Selection = useCallback((selection: SelectedComponent) => {
     handleCreateNewCourseXBlock({
       type: COMPONENT_TYPES.libraryV2,
       category: selection.blockType,
@@ -94,7 +129,7 @@ const AddComponent = ({
     closeAddLibraryContentModal();
   }, [usageId]);
 
-  const handleCreateNewXBlock = (type, moduleName) => {
+  const handleCreateNewXBlock = (type: string, moduleName?: string) => {
     switch (type) {
       case COMPONENT_TYPES.discussion:
       case COMPONENT_TYPES.dragAndDrop:
@@ -156,16 +191,16 @@ const AddComponent = ({
     }
   };
 
-  if (isUnitVerticalType || isSplitTestType) {
+  if (isUnitVerticalType || isSplitTestType || isProblemBankType) {
     return (
       <div className="py-4">
         {Object.keys(componentTemplates).length && isUnitVerticalType ? (
           <>
             <h5 className="h3 mb-4 text-center">{intl.formatMessage(messages.title)}</h5>
             <ul className="new-component-type list-unstyled m-0 d-flex flex-wrap justify-content-center">
-              {componentTemplates.map((component) => {
+              {componentTemplates.map((component: ComponentTemplateData) => {
                 const { type, displayName, beta } = component;
-                let modalParams;
+                let modalParams: { open: () => void, close: () => void, isOpen: boolean };
 
                 if (!component.templates.length) {
                   return null;
@@ -268,7 +303,7 @@ const AddComponent = ({
             />
           </div>
         </StandardModal>
-        {isXBlockEditorModalOpen && (
+        {isXBlockEditorModalOpen && courseId && blockType && newBlockId && (
           <div className="editor-page">
             <EditorPage
               courseId={courseId}
@@ -288,32 +323,4 @@ const AddComponent = ({
   return null;
 };
 
-AddComponent.propTypes = {
-  isSplitTestType: PropTypes.bool.isRequired,
-  isUnitVerticalType: PropTypes.bool.isRequired,
-  parentLocator: PropTypes.string.isRequired,
-  handleCreateNewCourseXBlock: PropTypes.func.isRequired,
-  addComponentTemplateData: {
-    blockId: PropTypes.string.isRequired,
-    model: PropTypes.shape({
-      displayName: PropTypes.string.isRequired,
-      category: PropTypes.string,
-      type: PropTypes.string.isRequired,
-      templates: PropTypes.arrayOf(
-        PropTypes.shape({
-          boilerplateName: PropTypes.string,
-          category: PropTypes.string,
-          displayName: PropTypes.string.isRequired,
-          supportLevel: PropTypes.oneOfType([PropTypes.string, PropTypes.bool]),
-        }),
-      ),
-      supportLegend: PropTypes.shape({
-        allowUnsupportedXblocks: PropTypes.bool,
-        documentationLabel: PropTypes.string,
-        showLegend: PropTypes.bool,
-      }),
-    }),
-  },
-};
-
 export default AddComponent;
diff --git a/src/course-unit/constants.js b/src/course-unit/constants.js
index 2da4dee302..04f9fa8893 100644
--- a/src/course-unit/constants.js
+++ b/src/course-unit/constants.js
@@ -41,6 +41,7 @@ export const getXBlockSupportMessages = (intl) => ({
 
 export const messageTypes = {
   refreshXBlock: 'refreshXBlock',
+  refreshIframe: 'refreshIframe',
   showMoveXBlockModal: 'showMoveXBlockModal',
   completeXBlockMoving: 'completeXBlockMoving',
   rollbackMovedXBlock: 'rollbackMovedXBlock',
diff --git a/src/course-unit/hooks.jsx b/src/course-unit/hooks.jsx
index dac48c5389..1109c5c8a6 100644
--- a/src/course-unit/hooks.jsx
+++ b/src/course-unit/hooks.jsx
@@ -72,6 +72,10 @@ export const useCourseUnit = ({ courseId, blockId }) => {
   const isUnitVerticalType = unitCategory === COURSE_BLOCK_NAMES.vertical.id;
   const isUnitLibraryType = unitCategory === COURSE_BLOCK_NAMES.libraryContent.id;
   const isSplitTestType = unitCategory === COURSE_BLOCK_NAMES.splitTest.id;
+  const isProblemBankType = [
+    COURSE_BLOCK_NAMES.legacyLibraryContent.id,
+    COURSE_BLOCK_NAMES.itembank.id,
+  ].includes(unitCategory);
 
   const headerNavigationsActions = {
     handleViewLive: () => {
@@ -254,6 +258,7 @@ export const useCourseUnit = ({ courseId, blockId }) => {
     isUnitVerticalType,
     isUnitLibraryType,
     isSplitTestType,
+    isProblemBankType,
     sharedClipboardData,
     showPasteXBlock,
     showPasteUnit,
diff --git a/src/course-unit/xblock-container-iframe/hooks/types.ts b/src/course-unit/xblock-container-iframe/hooks/types.ts
index 9d06598fba..45d7fee5fa 100644
--- a/src/course-unit/xblock-container-iframe/hooks/types.ts
+++ b/src/course-unit/xblock-container-iframe/hooks/types.ts
@@ -15,6 +15,7 @@ export type UseMessageHandlersTypes = {
   handleOpenManageTagsModal: (id: string) => void;
   handleShowProcessingNotification: (variant: string) => void;
   handleHideProcessingNotification: () => void;
+  handleRefreshIframe: () => void;
 };
 
 export type MessageHandlersTypes = Record<string, (payload: any) => void>;
diff --git a/src/course-unit/xblock-container-iframe/hooks/useMessageHandlers.tsx b/src/course-unit/xblock-container-iframe/hooks/useMessageHandlers.tsx
index afbab8a2a0..fdba8ecdc5 100644
--- a/src/course-unit/xblock-container-iframe/hooks/useMessageHandlers.tsx
+++ b/src/course-unit/xblock-container-iframe/hooks/useMessageHandlers.tsx
@@ -31,6 +31,7 @@ export const useMessageHandlers = ({
   handleShowProcessingNotification,
   handleHideProcessingNotification,
   handleEditXBlock,
+  handleRefreshIframe,
 }: UseMessageHandlersTypes): MessageHandlersTypes => {
   const { copyToClipboard } = useClipboard();
 
@@ -50,6 +51,7 @@ export const useMessageHandlers = ({
     [messageTypes.saveEditedXBlockData]: handleSaveEditedXBlockData,
     [messageTypes.studioAjaxError]: ({ error }) => handleResponseErrors(error, dispatch, updateSavingStatus),
     [messageTypes.refreshPositions]: handleFinishXBlockDragging,
+    [messageTypes.refreshIframe]: handleRefreshIframe,
     [messageTypes.openManageTags]: (payload) => handleOpenManageTagsModal(payload.contentId),
     [messageTypes.addNewComponent]: () => handleShowProcessingNotification(NOTIFICATION_MESSAGES.adding),
     [messageTypes.pasteNewComponent]: () => handleShowProcessingNotification(NOTIFICATION_MESSAGES.pasting),
diff --git a/src/course-unit/xblock-container-iframe/index.tsx b/src/course-unit/xblock-container-iframe/index.tsx
index 2507c2f8a1..5b67b340af 100644
--- a/src/course-unit/xblock-container-iframe/index.tsx
+++ b/src/course-unit/xblock-container-iframe/index.tsx
@@ -46,6 +46,8 @@ const XBlockContainerIframe: FC<XBlockContainerIframeProps> = ({
   const intl = useIntl();
   const dispatch = useDispatch();
 
+  // Useful to reload iframe
+  const [iframeKey, setIframeKey] = useState(0);
   const [isDeleteModalOpen, openDeleteModal, closeDeleteModal] = useToggle(false);
   const [isUnlinkModalOpen, openUnlinkModal, closeUnlinkModal] = useToggle(false);
   const [isConfigureModalOpen, openConfigureModal, closeConfigureModal] = useToggle(false);
@@ -182,6 +184,12 @@ const XBlockContainerIframe: FC<XBlockContainerIframeProps> = ({
     dispatch(hideProcessingNotification());
   };
 
+  const handleRefreshIframe = () => {
+    // Updating iframeKey forces the iframe to re-render.
+    /* istanbul ignore next */
+    setIframeKey((prev) => prev + 1);
+  };
+
   const messageHandlers = useMessageHandlers({
     courseId,
     dispatch,
@@ -199,6 +207,7 @@ const XBlockContainerIframe: FC<XBlockContainerIframeProps> = ({
     handleShowProcessingNotification,
     handleHideProcessingNotification,
     handleEditXBlock,
+    handleRefreshIframe,
   });
 
   useIframeMessages(messageHandlers);
@@ -268,6 +277,7 @@ const XBlockContainerIframe: FC<XBlockContainerIframeProps> = ({
         />
       ) : null}
       <iframe
+        key={iframeKey}
         ref={iframeRef}
         title={intl.formatMessage(messages.xblockIframeTitle)}
         name="xblock-iframe"
diff --git a/src/library-authoring/component-picker/ComponentPicker.tsx b/src/library-authoring/component-picker/ComponentPicker.tsx
index 00cab0630a..170de643d4 100644
--- a/src/library-authoring/component-picker/ComponentPicker.tsx
+++ b/src/library-authoring/component-picker/ComponentPicker.tsx
@@ -53,17 +53,10 @@ type ComponentPickerProps = {
   showOnlyPublished?: boolean,
   extraFilter?: string[],
   visibleTabs?: ContentType[],
-} & (
-  {
-    componentPickerMode?: 'single',
-    onComponentSelected?: ComponentSelectedEvent,
-    onChangeComponentSelection?: never,
-  } | {
-    componentPickerMode: 'multiple'
-    onComponentSelected?: never,
-    onChangeComponentSelection?: ComponentSelectionChangedEvent,
-  }
-);
+  componentPickerMode?: 'single' | 'multiple',
+  onComponentSelected?: ComponentSelectedEvent,
+  onChangeComponentSelection?: ComponentSelectionChangedEvent,
+};
 
 export const ComponentPicker: React.FC<ComponentPickerProps> = ({
   /** Restrict the component picker to a specific library */