diff --git a/src/main.ts b/src/main.ts
index db631a3..e3722b4 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -1176,6 +1176,8 @@ const SAMPLE_PROJECT = { name: '운곡교P1', bridge: '운곡교' } as const;
 function fillSampleNames(): void {
   $<HTMLInputElement>('project-name').value = SAMPLE_PROJECT.name;
   $<HTMLInputElement>('bridge-name').value = SAMPLE_PROJECT.bridge;
+  // Setting .value does not fire 'input', so the apply button must be refreshed here.
+  updateApply();
 }
 
 $<HTMLButtonElement>('pick-sample').addEventListener('click', async () => {