diff --git a/ext/js/language/dictionary-database-modifier.js b/ext/js/language/dictionary-database-modifier.js
index 3b100fae..055c4769 100644
--- a/ext/js/language/dictionary-database-modifier.js
+++ b/ext/js/language/dictionary-database-modifier.js
@@ -25,12 +25,22 @@ class DictionaryDatabaseModifier {
     }
 
     importDictionary(archiveContent, details, onProgress) {
-        return this._invoke('importDictionary', {details, archiveContent}, [archiveContent], onProgress);
+        return this._invoke(
+            'importDictionary',
+            {details, archiveContent},
+            [archiveContent],
+            onProgress,
+            this._formatimportDictionaryResult.bind(this)
+        );
+    }
+
+    deleteDictionary(dictionaryTitle, onProgress) {
+        return this._invoke('deleteDictionary', {dictionaryTitle}, [], onProgress);
     }
 
     // Private
 
-    _invoke(action, params, transfer, onProgress) {
+    _invoke(action, params, transfer, onProgress, formatResult) {
         return new Promise((resolve, reject) => {
             const worker = new Worker('/js/language/dictionary-worker-main.js', {});
             const details = {
@@ -39,7 +49,8 @@ class DictionaryDatabaseModifier {
                 resolve,
                 reject,
                 onMessage: null,
-                onProgress
+                onProgress,
+                formatResult
             };
             const onMessage = this._onMessage.bind(this, details);
             details.onMessage = onMessage;
@@ -54,15 +65,17 @@ class DictionaryDatabaseModifier {
         switch (action) {
             case 'complete':
                 {
-                    const {worker, resolve, reject, onMessage} = details;
+                    const {worker, resolve, reject, onMessage, formatResult} = details;
                     details.complete = true;
                     details.worker = null;
                     details.resolve = null;
                     details.reject = null;
                     details.onMessage = null;
+                    details.onProgress = null;
+                    details.formatResult = null;
                     worker.removeEventListener('message', onMessage);
                     worker.terminate();
-                    this._onMessageComplete(params, resolve, reject);
+                    this._onMessageComplete(params, resolve, reject, formatResult);
                 }
                 break;
             case 'progress':
@@ -74,12 +87,21 @@ class DictionaryDatabaseModifier {
         }
     }
 
-    _onMessageComplete(params, resolve, reject) {
+    _onMessageComplete(params, resolve, reject, formatResult) {
         const {error} = params;
         if (typeof error !== 'undefined') {
             reject(deserializeError(error));
         } else {
-            resolve(this._formatResult(params.result));
+            let {result} = params;
+            try {
+                if (typeof formatResult === 'function') {
+                    result = formatResult(result);
+                }
+            } catch (e) {
+                reject(e);
+                return;
+            }
+            resolve(result);
         }
     }
 
@@ -101,9 +123,8 @@ class DictionaryDatabaseModifier {
         worker.postMessage({action: 'getImageResolution.response', params: response});
     }
 
-    _formatResult(data) {
-        const {result, errors} = data;
-        const errors2 = errors.map((error) => deserializeError(error));
-        return {result, errors: errors2};
+    _formatimportDictionaryResult(result) {
+        result.errors = result.errors.map((error) => deserializeError(error));
+        return result;
     }
 }
diff --git a/ext/js/language/dictionary-worker.js b/ext/js/language/dictionary-worker.js
index 5c482178..dc546657 100644
--- a/ext/js/language/dictionary-worker.js
+++ b/ext/js/language/dictionary-worker.js
@@ -36,7 +36,10 @@ class DictionaryWorker {
         const {action, params} = e.data;
         switch (action) {
             case 'importDictionary':
-                this._onImportDictionary(params);
+                this._onMessageWithProgress(params, this._importDictionary.bind(this));
+                break;
+            case 'deleteDictionary':
+                this._onMessageWithProgress(params, this._deleteDictionary.bind(this));
                 break;
             case 'getImageResolution.response':
                 this._mediaLoader.handleMessage(params);
@@ -44,7 +47,7 @@ class DictionaryWorker {
         }
     }
 
-    async _onImportDictionary({details, archiveContent}) {
+    async _onMessageWithProgress(params, handler) {
         const onProgress = (...args) => {
             self.postMessage({
                 action: 'progress',
@@ -53,7 +56,7 @@ class DictionaryWorker {
         };
         let response;
         try {
-            const result = await this._importDictionary(archiveContent, details, onProgress);
+            const result = await handler(params, onProgress);
             response = {result};
         } catch (e) {
             response = {error: serializeError(e)};
@@ -61,11 +64,11 @@ class DictionaryWorker {
         self.postMessage({action: 'complete', params: response});
     }
 
-    async _importDictionary(archiveContent, importDetails, onProgress) {
+    async _importDictionary({details, archiveContent}, onProgress) {
         const dictionaryDatabase = await this._getPreparedDictionaryDatabase();
         try {
             const dictionaryImporter = new DictionaryImporter(this._mediaLoader, onProgress);
-            const {result, errors} = await dictionaryImporter.importDictionary(dictionaryDatabase, archiveContent, importDetails);
+            const {result, errors} = await dictionaryImporter.importDictionary(dictionaryDatabase, archiveContent, details);
             return {
                 result,
                 errors: errors.map((error) => serializeError(error))
@@ -75,6 +78,15 @@ class DictionaryWorker {
         }
     }
 
+    async _deleteDictionary({dictionaryTitle}, onProgress) {
+        const dictionaryDatabase = await this._getPreparedDictionaryDatabase();
+        try {
+            return await dictionaryDatabase.deleteDictionary(dictionaryTitle, {rate: 1000}, onProgress);
+        } finally {
+            dictionaryDatabase.close();
+        }
+    }
+
     async _getPreparedDictionaryDatabase() {
         const dictionaryDatabase = new DictionaryDatabase();
         await dictionaryDatabase.prepare();
diff --git a/ext/js/pages/settings/dictionary-controller.js b/ext/js/pages/settings/dictionary-controller.js
index 47b256d8..8df4b6bd 100644
--- a/ext/js/pages/settings/dictionary-controller.js
+++ b/ext/js/pages/settings/dictionary-controller.js
@@ -16,7 +16,7 @@
  */
 
 /* global
- * DictionaryDatabase
+ * DictionaryDatabaseModifier
  */
 
 class DictionaryEntry {
@@ -679,19 +679,9 @@ class DictionaryController {
     }
 
     async _deleteDictionaryInternal(dictionaryTitle, onProgress) {
-        const dictionaryDatabase = await this._getPreparedDictionaryDatabase();
-        try {
-            await dictionaryDatabase.deleteDictionary(dictionaryTitle, {rate: 1000}, onProgress);
-            yomichan.api.triggerDatabaseUpdated('dictionary', 'delete');
-        } finally {
-            dictionaryDatabase.close();
-        }
-    }
-
-    async _getPreparedDictionaryDatabase() {
-        const dictionaryDatabase = new DictionaryDatabase();
-        await dictionaryDatabase.prepare();
-        return dictionaryDatabase;
+        const dictionaryDatabaseModifier = new DictionaryDatabaseModifier();
+        await dictionaryDatabaseModifier.deleteDictionary(dictionaryTitle, onProgress);
+        yomichan.api.triggerDatabaseUpdated('dictionary', 'delete');
     }
 
     async _deleteDictionarySettings(dictionaryTitle) {
diff --git a/ext/settings.html b/ext/settings.html
index 55704f53..576b8fc7 100644
--- a/ext/settings.html
+++ b/ext/settings.html
@@ -3483,7 +3483,6 @@
 <script src="/js/general/object-property-accessor.js"></script>
 <script src="/js/general/task-accumulator.js"></script>
 <script src="/js/input/hotkey-util.js"></script>
-<script src="/js/language/dictionary-database.js"></script>
 <script src="/js/language/dictionary-database-modifier.js"></script>
 <script src="/js/language/dictionary-importer-media-loader.js"></script>
 <script src="/js/language/sandbox/dictionary-data-util.js"></script>
diff --git a/ext/welcome.html b/ext/welcome.html
index 9a6ba09d..e03ae5ec 100644
--- a/ext/welcome.html
+++ b/ext/welcome.html
@@ -405,7 +405,6 @@
 <script src="/js/general/object-property-accessor.js"></script>
 <script src="/js/general/task-accumulator.js"></script>
 <script src="/js/input/hotkey-util.js"></script>
-<script src="/js/language/dictionary-database.js"></script>
 <script src="/js/language/dictionary-database-modifier.js"></script>
 <script src="/js/language/dictionary-importer-media-loader.js"></script>
 <script src="/js/media/media-util.js"></script>