diff --git a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
index b8e33739..164e9b32 100644
--- a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
+++ b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
@@ -283,7 +283,15 @@ describe('PersonMentionEditor — AC-2/3: search input drives fetch', () => {
 
 		const fetchesBeforeClear = fetchMock.mock.calls.length;
 
-		await userEvent.clear(page.getByRole('searchbox'));
+		// `fill('')` atomically sets the input value in a single input event —
+		// same rationale as the `fill('Walter')` call above. `userEvent.clear`
+		// deletes per-keystroke, so intermediate values 'Au'/'A' transit through
+		// the bound `searchQuery` and each schedules a debounced fetch. Under
+		// CI-runner jitter, if two consecutive keystrokes land more than
+		// SEARCH_DEBOUNCE_MS (150 ms) apart, an intermediate timer fires before
+		// the input reaches '' and adds a phantom call — unrelated to the
+		// contract under test, which is "empty query => no fetch".
+		await page.getByRole('searchbox').fill('');
 
 		// Negative assertion: wait past the debounce window to confirm no
 		// trailing fetch was scheduled. Removing this wait would mask a