diff --git a/packages/mermaid/src/mermaidAPI.spec.ts b/packages/mermaid/src/mermaidAPI.spec.ts
index e51d419d3..1a2289df2 100644
--- a/packages/mermaid/src/mermaidAPI.spec.ts
+++ b/packages/mermaid/src/mermaidAPI.spec.ts
@@ -67,10 +67,11 @@ vi.mock('stylis', () => {
 
 import { compile, serialize } from 'stylis';
 import { Diagram } from './Diagram.js';
-import { decodeEntities, encodeEntities } from './utils.js';
-import { toBase64 } from './utils/base64.js';
 import { ClassDB } from './diagrams/class/classDb.js';
 import { FlowDB } from './diagrams/flowchart/flowDb.js';
+import { SequenceDB } from './diagrams/sequence/sequenceDb.js';
+import { decodeEntities, encodeEntities } from './utils.js';
+import { toBase64 } from './utils/base64.js';
 
 /**
  * @see https://vitest.dev/guide/mocking.html Mock part of a module
@@ -899,28 +900,18 @@ graph TD;A--x|text including URL space|B;`)
       );
       const sequenceDiagram2 = await mermaidAPI.getDiagramFromText(
         `sequenceDiagram
+        actor A1
     Alice->>+John: Hello John, how are you?
     Alice->>+John: John, can you hear me?
     John-->>-Alice: Hi Alice, I can hear you!
     John-->>-Alice: I feel great!`
       );
-      // Since sequenceDiagram will return same Db object each time, we can compare the db to be same.
-      expect(sequenceDiagram1.db).toBe(sequenceDiagram2.db);
+
+      // Since sequenceDiagram will return new Db object each time, we can compare the db to be different.
+      expect(sequenceDiagram1.db).not.toBe(sequenceDiagram2.db);
+      assert(sequenceDiagram1.db instanceof SequenceDB);
+      assert(sequenceDiagram2.db instanceof SequenceDB);
+      expect(sequenceDiagram1.db.getActors()).not.toEqual(sequenceDiagram2.db.getActors());
     });
   });
-
-  // Sequence Diagram currently uses a singleton DB, so this test will fail
-  it.fails('should not modify db when rendering different sequence diagrams', async () => {
-    const sequenceDiagram1 = await mermaidAPI.getDiagramFromText(
-      `sequenceDiagram
-    Alice->>Bob: Hello Bob, how are you?
-    Bob-->>John: How about you John?`
-    );
-    const sequenceDiagram2 = await mermaidAPI.getDiagramFromText(
-      `sequenceDiagram
-    Alice->>Bob: Hello Bob, how are you?
-    Bob-->>John: How about you John?`
-    );
-    expect(sequenceDiagram1.db).not.toBe(sequenceDiagram2.db);
-  });
 });