diff --git a/packages/mermaid/src/tests/MockedD3.ts b/packages/mermaid/src/tests/MockedD3.ts
index 6d8d721e0..4254b3a1f 100644
--- a/packages/mermaid/src/tests/MockedD3.ts
+++ b/packages/mermaid/src/tests/MockedD3.ts
@@ -133,6 +133,7 @@ export class MockedD3 {
   // --------------------------------------------------------------------------------
   // The following functions are here for completeness.  They simply return a vi.fn()
 
+  remove = vi.fn();
   insertBefore = vi.fn();
   curveBasis = vi.fn();
   curveBasisClosed = vi.fn();