diff --git a/packages/netlify-cms-core/src/components/Editor/EditorPreviewPane/EditorPreview.js b/packages/netlify-cms-core/src/components/Editor/EditorPreviewPane/EditorPreview.js
index 52cec09f..b89b07f8 100644
--- a/packages/netlify-cms-core/src/components/Editor/EditorPreviewPane/EditorPreview.js
+++ b/packages/netlify-cms-core/src/components/Editor/EditorPreviewPane/EditorPreview.js
@@ -8,7 +8,7 @@ function isVisible(field) {
 }
 
 const PreviewContainer = styled.div`
-  fontFamily: Roboto, "Helvetica Neue", HelveticaNeue, Helvetica, Arial, sans-serif;
+  font-family: Roboto, "Helvetica Neue", HelveticaNeue, Helvetica, Arial, sans-serif;
 `
 
 /**
diff --git a/packages/netlify-cms-core/src/components/Editor/EditorToolbar.js b/packages/netlify-cms-core/src/components/Editor/EditorToolbar.js
index d9150e3c..2f5c29cc 100644
--- a/packages/netlify-cms-core/src/components/Editor/EditorToolbar.js
+++ b/packages/netlify-cms-core/src/components/Editor/EditorToolbar.js
@@ -273,7 +273,7 @@ export default class EditorToolbar extends React.Component {
       isNewEntry,
     } = this.props;
     if (currentStatus) {
-      return [
+      return (<>
         <ToolbarDropdown
           dropdownTopOverlap="40px"
           dropdownWidth="120px"
@@ -296,7 +296,7 @@ export default class EditorToolbar extends React.Component {
             onClick={() => onChangeStatus('PENDING_PUBLISH')}
             icon={currentStatus === status.get('PENDING_PUBLISH') && 'check'}
           />
-        </ToolbarDropdown>,
+        </ToolbarDropdown>
         <ToolbarDropdown
           dropdownTopOverlap="40px"
           dropdownWidth="150px"
@@ -311,7 +311,7 @@ export default class EditorToolbar extends React.Component {
               : null
           }
         </ToolbarDropdown>
-      ];
+      </>);
     }
 
     if (!isNewEntry) {
diff --git a/packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownControl.js b/packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownControl.js
index 2787f34a..f0930514 100644
--- a/packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownControl.js
+++ b/packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownControl.js
@@ -2,7 +2,7 @@ import React from 'react';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 
 export default function UnknownControl({ field }) {
-  return <div>No control for widget '{field.get('widget')}'.</div>;
+  return <div>{`No control for widget '${field.get('widget')}'.`}</div>;
 }
 
 UnknownControl.propTypes = {
diff --git a/packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryCardGrid.js b/packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryCardGrid.js
index 398422ce..490325ae 100644
--- a/packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryCardGrid.js
+++ b/packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryCardGrid.js
@@ -1,6 +1,7 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import styled from 'react-emotion'
+import Waypoint from 'react-waypoint';
 import MediaLibraryCard from './MediaLibraryCard';
 import { colors } from 'netlify-cms-ui-default';
 
diff --git a/packages/netlify-cms-core/src/components/UI/ErrorBoundary.js b/packages/netlify-cms-core/src/components/UI/ErrorBoundary.js
index 354b10d6..309abdf6 100644
--- a/packages/netlify-cms-core/src/components/UI/ErrorBoundary.js
+++ b/packages/netlify-cms-core/src/components/UI/ErrorBoundary.js
@@ -37,8 +37,8 @@ export class ErrorBoundary extends React.Component {
       <div className={styles.errorBoundary}>
         <h1 className={styles.errorBoundaryText}>Sorry!</h1>
         <p>
-          <span>There's been an error - please </span>
-          <a href={ISSUE_URL} target="_blank" className={styles.errorBoundaryText}>report it</a>!
+          <span>{"There's been an error - please "}</span>
+          <a href={ISSUE_URL} target="_blank" rel="noopener noreferrer" className={styles.errorBoundaryText}>report it</a>!
         </p>
         <p>{errorMessage}</p>
       </div>
diff --git a/packages/netlify-cms-core/src/components/Workflow/WorkflowCard.js b/packages/netlify-cms-core/src/components/Workflow/WorkflowCard.js
index c4fe44ce..3034ddb0 100644
--- a/packages/netlify-cms-core/src/components/Workflow/WorkflowCard.js
+++ b/packages/netlify-cms-core/src/components/Workflow/WorkflowCard.js
@@ -21,7 +21,6 @@ const styles = {
 const WorkflowLink = styled(Link)`
   display: block;
   padding: 0 18px 18px;
-  padding: 0 18px 18px;
   height: 200px;
   overflow: hidden;
 `
diff --git a/packages/netlify-cms-core/src/reducers/collections.js b/packages/netlify-cms-core/src/reducers/collections.js
index d5c7288b..5b8c7af1 100644
--- a/packages/netlify-cms-core/src/reducers/collections.js
+++ b/packages/netlify-cms-core/src/reducers/collections.js
@@ -8,7 +8,7 @@ import { formatToExtension } from 'Formats/formats';
 
 const collections = (state = null, action) => {
   switch (action.type) {
-    case CONFIG_SUCCESS:
+    case CONFIG_SUCCESS: {
       const configCollections = action.payload ? action.payload.get('collections') : List();
       return configCollections
         .toOrderedMap()
@@ -21,6 +21,7 @@ const collections = (state = null, action) => {
           }
         })
         .mapKeys((key, collection) => collection.get('name'));
+    }
     default:
       return state;
   }
diff --git a/packages/netlify-cms-core/src/reducers/editorialWorkflow.js b/packages/netlify-cms-core/src/reducers/editorialWorkflow.js
index 7642f315..f9bec559 100644
--- a/packages/netlify-cms-core/src/reducers/editorialWorkflow.js
+++ b/packages/netlify-cms-core/src/reducers/editorialWorkflow.js
@@ -22,13 +22,14 @@ import { CONFIG_SUCCESS } from 'Actions/config';
 
 const unpublishedEntries = (state = Map(), action) => {
   switch (action.type) {
-    case CONFIG_SUCCESS:
+    case CONFIG_SUCCESS: {
       const publishMode = action.payload && action.payload.get('publish_mode');
       if (publishMode === EDITORIAL_WORKFLOW) {
         //  Editorial workflow state is explicetelly initiated after the config.
         return Map({ entities: Map(), pages: Map() });
       }
       return state;
+    }
     case UNPUBLISHED_ENTRY_REQUEST:
       return state.setIn(['entities', `${ action.payload.collection }.${ action.payload.slug }`, 'isFetching'], true);
 
diff --git a/packages/netlify-cms-core/src/reducers/integrations.js b/packages/netlify-cms-core/src/reducers/integrations.js
index 58cc27e1..776304df 100644
--- a/packages/netlify-cms-core/src/reducers/integrations.js
+++ b/packages/netlify-cms-core/src/reducers/integrations.js
@@ -3,7 +3,7 @@ import { CONFIG_SUCCESS } from 'Actions/config';
 
 const integrations = (state = null, action) => {
   switch (action.type) {
-    case CONFIG_SUCCESS:
+    case CONFIG_SUCCESS: {
       const integrations = action.payload.get('integrations', List()).toJS() || [];
       const newState = integrations.reduce((acc, integration) => {
         const { hooks, collections, provider, ...providerData } = integration;
@@ -23,6 +23,7 @@ const integrations = (state = null, action) => {
         return acc;
       }, { providers:{}, hooks: {} });
       return fromJS(newState);
+    }
     default:
       return state;
   }
diff --git a/packages/netlify-cms-widget-markdown/src/MarkdownControl/Toolbar.js b/packages/netlify-cms-widget-markdown/src/MarkdownControl/Toolbar.js
index 070af14c..e74ea89b 100644
--- a/packages/netlify-cms-widget-markdown/src/MarkdownControl/Toolbar.js
+++ b/packages/netlify-cms-widget-markdown/src/MarkdownControl/Toolbar.js
@@ -55,7 +55,7 @@ const ToolbarToggleLabel = styled.span`
 
 export default class Toolbar extends React.Component {
   static propTypes = {
-    buttons: PropTypes.object,
+    buttons: ImmutablePropTypes.list,
     onToggleMode: PropTypes.func.isRequired,
     rawMode: PropTypes.bool,
     plugins: ImmutablePropTypes.map,
@@ -63,7 +63,6 @@ export default class Toolbar extends React.Component {
     onAddAsset: PropTypes.func,
     getAsset: PropTypes.func,
     disabled: PropTypes.bool,
-    buttons: ImmutablePropTypes.list
   };
 
   constructor(props) {
diff --git a/packages/netlify-cms-widget-markdown/src/serializers/remarkShortcodes.js b/packages/netlify-cms-widget-markdown/src/serializers/remarkShortcodes.js
index 2b07759a..ea953039 100644
--- a/packages/netlify-cms-widget-markdown/src/serializers/remarkShortcodes.js
+++ b/packages/netlify-cms-widget-markdown/src/serializers/remarkShortcodes.js
@@ -45,7 +45,7 @@ export default function remarkShortcodes({ plugins }) {
      * included. Otherwise, return the original node.
      */
     return matchIsValid ? createShortcodeNode(text, plugin, match) : node;
-  };
+  }
 
   /**
    * Ensure that the node and it's children are acceptable types to contain