diff --git a/ext/bg/js/database.js b/ext/bg/js/database.js
index 469b1311..9e90e6de 100644
--- a/ext/bg/js/database.js
+++ b/ext/bg/js/database.js
@@ -233,7 +233,7 @@ class Database {
             throw 'Database not initialized';
         }
 
-        const indexDataLoaded = async summary => {
+        const indexDataValid = async summary => {
             if (summary.version > 2) {
                 throw 'Unsupported dictionary version';
             }
@@ -242,7 +242,9 @@ class Database {
             if (count > 0) {
                 throw 'Dictionary is already imported';
             }
+        };
 
+        const indexDataLoaded = async summary => {
             await this.db.dictionaries.add(summary);
         };
 
@@ -280,6 +282,8 @@ class Database {
                 }
             }
 
+            summary.hasSequences = rows.every(row => row.sequence >= 0);
+
             await this.db.terms.bulkAdd(rows);
         };
 
@@ -377,6 +381,7 @@ class Database {
 
         return await Database.importDictionaryZip(
             archive,
+            indexDataValid,
             indexDataLoaded,
             termDataLoaded,
             termMetaDataLoaded,
@@ -388,6 +393,7 @@ class Database {
 
     static async importDictionaryZip(
         archive,
+        indexDataValid,
         indexDataLoaded,
         termDataLoaded,
         termMetaDataLoaded,
@@ -413,9 +419,7 @@ class Database {
             version: index.format || index.version
         };
 
-        if (indexDataLoaded) {
-            await indexDataLoaded(summary);
-        }
+        await indexDataValid(summary);
 
         const buildTermBankName      = index => `term_bank_${index + 1}.json`;
         const buildTermMetaBankName  = index => `term_meta_bank_${index + 1}.json`;
@@ -472,6 +476,10 @@ class Database {
         await loadBank(summary, buildKanjiMetaBankName, kanjiMetaBankCount, kanjiMetaDataLoaded);
         await loadBank(summary, buildTagBankName, tagBankCount, tagDataLoaded);
 
+        if (indexDataLoaded) {
+            await indexDataLoaded(summary);
+        }
+
         return summary;
     }
 }