diff --git a/app.py b/app.py
index fb6fbca..fbf404a 100644
--- a/app.py
+++ b/app.py
@@ -4444,7 +4444,7 @@ def _prefer_detected_model(provider: str, models: list[str], manual_option: str)
     provider_slug = provider_state_slug(provider)
     choice_key = f"model_choice_{provider_slug}"
     current_choice = st.session_state.get(choice_key)
-    if current_choice in models:
+    if current_choice == manual_option or current_choice in models:
         return
     preferred = str(
         st.session_state.get(f"model_manual_{provider_slug}", "")
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 9c81450..6aa6003 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,2 +1,3 @@
 -r requirements.txt
+httpx>=0.28.1,<1.0.0
 pytest>=9.1.1,<10.0
diff --git a/tests/test_app_smoke.py b/tests/test_app_smoke.py
index 97a44af..0325b26 100644
--- a/tests/test_app_smoke.py
+++ b/tests/test_app_smoke.py
@@ -35,6 +35,10 @@ def test_app_starts_without_contacting_a_model() -> None:
 def test_chat_submission_is_preserved_without_a_selected_model() -> None:
     app_path = Path(__file__).resolve().parents[1] / "app.py"
     app = AppTest.from_file(str(app_path)).run(timeout=20)
+    model_choice = next(
+        item for item in app.selectbox if item.label == "已检测到的模型"
+    )
+    model_choice.set_value("手动输入…").run(timeout=20)
     model = next(item for item in app.text_input if item.label == "Model Name")
     model.set_value("").run(timeout=20)
     question = next(item for item in app.text_area if item.label == "继续回复 JARVIS")