diff --git a/src/renderer/src/components/terminal-pane/terminal-ime-deferred-newline.test.ts b/src/renderer/src/components/terminal-pane/terminal-ime-deferred-newline.test.ts
index ff5098bc210..4b338509c11 100644
--- a/src/renderer/src/components/terminal-pane/terminal-ime-deferred-newline.test.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-ime-deferred-newline.test.ts
@@ -355,7 +355,9 @@ describe('isTerminalImeProcessEnter', () => {
     { altKey: true },
     // Windows hands every IME-consumed keydown the same Process/229 shape, so a shifted
     // jamo (ㅃ on KeyQ) differs from the committing Enter only by `code`.
-    { code: 'KeyQ' }
+    { code: 'KeyQ' },
+    // Same shape from a Japanese IME: Shift+Left/Right resizes the conversion segment.
+    { code: 'ArrowLeft' }
   ])('rejects a non-IME or ambiguous Process key', (override) => {
     expect(isTerminalImeProcessEnter(event(override))).toBe(false)
   })