diff --git a/frontend/src/Components/Filter/Builder/FilterBuilderModalContent.js b/frontend/src/Components/Filter/Builder/FilterBuilderModalContent.js
index d33f4d4fb..0c4a31657 100644
--- a/frontend/src/Components/Filter/Builder/FilterBuilderModalContent.js
+++ b/frontend/src/Components/Filter/Builder/FilterBuilderModalContent.js
@@ -1,3 +1,4 @@
+import { maxBy } from 'lodash';
 import PropTypes from 'prop-types';
 import React, { Component } from 'react';
 import FormInputGroup from 'Components/Form/FormInputGroup';
@@ -50,7 +51,7 @@ class FilterBuilderModalContent extends Component {
       if (id) {
         dispatchSetFilter({ selectedFilterKey: id });
       } else {
-        const last = customFilters[customFilters.length -1];
+        const last = maxBy(customFilters, 'id');
         dispatchSetFilter({ selectedFilterKey: last.id });
       }
 
@@ -108,7 +109,7 @@ class FilterBuilderModalContent extends Component {
       this.setState({
         labelErrors: [
           {
-            message: 'Label is required'
+            message: translate('LabelIsRequired')
           }
         ]
       });
@@ -146,7 +147,7 @@ class FilterBuilderModalContent extends Component {
     return (
       <ModalContent onModalClose={onModalClose}>
         <ModalHeader>
-          Custom Filter
+          {translate('CustomFilter')}
         </ModalHeader>
 
         <ModalBody>
@@ -166,7 +167,9 @@ class FilterBuilderModalContent extends Component {
             </div>
           </div>
 
-          <div className={styles.label}>{translate('Filters')}</div>
+          <div className={styles.label}>
+            {translate('Filters')}
+          </div>
 
           <div className={styles.rows}>
             {
diff --git a/frontend/src/Components/Filter/CustomFilters/CustomFilter.js b/frontend/src/Components/Filter/CustomFilters/CustomFilter.js
index 7407f729a..9f378d5a2 100644
--- a/frontend/src/Components/Filter/CustomFilters/CustomFilter.js
+++ b/frontend/src/Components/Filter/CustomFilters/CustomFilter.js
@@ -37,8 +37,8 @@ class CustomFilter extends Component {
       dispatchSetFilter
     } = this.props;
 
-    // Assume that delete and then unmounting means the delete was successful.
-    // Moving this check to a ancestor would be more accurate, but would have
+    // Assume that delete and then unmounting means the deletion was successful.
+    // Moving this check to an ancestor would be more accurate, but would have
     // more boilerplate.
     if (this.state.isDeleting && id === selectedFilterKey) {
       dispatchSetFilter({ selectedFilterKey: 'all' });
diff --git a/src/NzbDrone.Core/Localization/Core/en.json b/src/NzbDrone.Core/Localization/Core/en.json
index 520837a8f..b903ae491 100644
--- a/src/NzbDrone.Core/Localization/Core/en.json
+++ b/src/NzbDrone.Core/Localization/Core/en.json
@@ -245,6 +245,7 @@
   "CreateEmptyArtistFoldersHelpText": "Create missing artist folders during disk scan",
   "CreateGroup": "Create group",
   "Custom": "Custom",
+  "CustomFilter": "Custom Filter",
   "CustomFilters": "Custom Filters",
   "CustomFormat": "Custom Format",
   "CustomFormatRequiredHelpText": "This {0} condition must match for the custom format to apply.  Otherwise a single {0} match is sufficient.",
@@ -482,8 +483,8 @@
   "FormatAgeHours": "hours",
   "FormatAgeMinute": "minute",
   "FormatAgeMinutes": "minutes",
-  "FormatDateTimeRelative": "{relativeDay}, {formattedDate} {formattedTime}",
   "FormatDateTime": "{formattedDate} {formattedTime}",
+  "FormatDateTimeRelative": "{relativeDay}, {formattedDate} {formattedTime}",
   "FormatRuntimeHours": "{hours}h",
   "FormatRuntimeMinutes": "{minutes}m",
   "FormatShortTimeSpanHours": "{hours} hour(s)",
@@ -609,6 +610,7 @@
   "ItsEasyToAddANewArtistJustStartTypingTheNameOfTheArtistYouWantToAdd": "It's easy to add a new artist, just start typing the name of the artist you want to add.",
   "KeyboardShortcuts": "Keyboard Shortcuts",
   "Label": "Label",
+  "LabelIsRequired": "Label is required",
   "Language": "Language",
   "Large": "Large",
   "LastAlbum": "Last Album",