diff --git a/src/mlpccg/database.ts b/src/mlpccg/database.ts
index 088f5ab..a9dd537 100644
--- a/src/mlpccg/database.ts
+++ b/src/mlpccg/database.ts
@@ -20,7 +20,9 @@ class CardDatabase extends Dexie {
 export let Database: CardDatabase | null = null;
 
 export function initDB() {
-  Database = new CardDatabase();
+  if (Database == null) {
+    Database = new CardDatabase();
+  }
 }
 
 export async function getCards(filter: CardFilter) {
diff --git a/src/testing/IDBShim.ts b/src/testing/IDBShim.ts
new file mode 100644
index 0000000..59fdb2c
--- /dev/null
+++ b/src/testing/IDBShim.ts
@@ -0,0 +1,11 @@
+import Dexie from "dexie";
+
+let init = false;
+
+export function setupIDBShim() {
+  if (!init) {
+    const setGlobalVars = require("indexeddbshim");
+    setGlobalVars(Dexie.dependencies);
+    init = true;
+  }
+}
diff --git a/src/tests/unit/database.spec.ts b/src/tests/unit/database.spec.ts
index b87cf75..1bb70a5 100644
--- a/src/tests/unit/database.spec.ts
+++ b/src/tests/unit/database.spec.ts
@@ -1,7 +1,7 @@
 import { loadSets, getCards, Database, initDB, cardFullName } from "@/mlpccg";
-import Dexie from "dexie";
-const setGlobalVars = require("indexeddbshim");
-setGlobalVars(Dexie.dependencies);
+import { setupIDBShim } from "@/testing/IDBShim";
+
+setupIDBShim();
 
 describe("mlpccg/Database", () => {
   beforeAll(async () => {