diff --git a/packages/mermaid/src/diagrams/flowchart/parser/flow-md-string.spec.js b/packages/mermaid/src/diagrams/flowchart/parser/flow-md-string.spec.js
index 005d257e0..0e6efaef1 100644
--- a/packages/mermaid/src/diagrams/flowchart/parser/flow-md-string.spec.js
+++ b/packages/mermaid/src/diagrams/flowchart/parser/flow-md-string.spec.js
@@ -1,6 +1,6 @@
-import flowDb from '../flowDb';
-import flow from './flow';
-import { setConfig } from '../../../config';
+import flowDb from '../flowDb.js';
+import flow from './flow.jison';
+import { setConfig } from '../../../config.js';
 
 setConfig({
   securityLevel: 'strict',
diff --git a/packages/mermaid/src/mermaid.spec.ts b/packages/mermaid/src/mermaid.spec.ts
index b6acd17cb..e27428545 100644
--- a/packages/mermaid/src/mermaid.spec.ts
+++ b/packages/mermaid/src/mermaid.spec.ts
@@ -9,7 +9,7 @@ beforeAll(async () => {
 });
 const spyOn = vi.spyOn;
 
-vi.mock('./mermaidAPI');
+vi.mock('./mermaidAPI.js');
 
 afterEach(() => {
   vi.clearAllMocks();