diff --git a/app/src/main/java/acr/browser/lightning/database/bookmark/BookmarkDatabase.java b/app/src/main/java/acr/browser/lightning/database/bookmark/BookmarkDatabase.java
index bb3b929..ed66526 100644
--- a/app/src/main/java/acr/browser/lightning/database/bookmark/BookmarkDatabase.java
+++ b/app/src/main/java/acr/browser/lightning/database/bookmark/BookmarkDatabase.java
@@ -75,7 +75,7 @@ public class BookmarkDatabase extends SQLiteOpenHelper implements BookmarkModel
      */
     @WorkerThread
     @NonNull
-    private SQLiteDatabase lazyDatabase() {
+    private synchronized SQLiteDatabase lazyDatabase() {
         if (mDatabase == null || !mDatabase.isOpen()) {
             mDatabase = getWritableDatabase();
         }
diff --git a/app/src/main/java/acr/browser/lightning/database/downloads/DownloadsDatabase.java b/app/src/main/java/acr/browser/lightning/database/downloads/DownloadsDatabase.java
index a14faff..895205f 100644
--- a/app/src/main/java/acr/browser/lightning/database/downloads/DownloadsDatabase.java
+++ b/app/src/main/java/acr/browser/lightning/database/downloads/DownloadsDatabase.java
@@ -68,7 +68,7 @@ public class DownloadsDatabase extends SQLiteOpenHelper implements DownloadsMode
      */
     @WorkerThread
     @NonNull
-    private SQLiteDatabase lazyDatabase() {
+    private synchronized SQLiteDatabase lazyDatabase() {
         if (mDatabase == null || !mDatabase.isOpen()) {
             mDatabase = getWritableDatabase();
         }
diff --git a/app/src/main/java/acr/browser/lightning/database/history/HistoryDatabase.java b/app/src/main/java/acr/browser/lightning/database/history/HistoryDatabase.java
index b61fa16..8ceab08 100644
--- a/app/src/main/java/acr/browser/lightning/database/history/HistoryDatabase.java
+++ b/app/src/main/java/acr/browser/lightning/database/history/HistoryDatabase.java
@@ -92,7 +92,7 @@ public class HistoryDatabase extends SQLiteOpenHelper implements HistoryModel {
 
     @WorkerThread
     @NonNull
-    private SQLiteDatabase lazyDatabase() {
+    private synchronized SQLiteDatabase lazyDatabase() {
         if (mDatabase == null || !mDatabase.isOpen()) {
             mDatabase = this.getWritableDatabase();
         }