Update app.py

app.py

@@ -163,6 +163,11 @@ def download_threads_as_pdf(chat_threads):
         for msg in chats:
             role = "You" if msg["role"] == "user" else "Assistant"
             text = f"{role}: {msg['content']}"
+            # Safely encode for Latin-1 by replacing unknown characters
+            try:
+                text = text.encode('latin-1').decode('latin-1')
+            except UnicodeEncodeError:
+                text = text.encode('latin-1', 'replace').decode('latin-1')
             pdf.multi_cell(0, 10, text)
         pdf.ln(5)
     pdf_output = BytesIO()
@@ -171,6 +176,7 @@ def download_threads_as_pdf(chat_threads):
     pdf_output.seek(0)
     return pdf_output
 
+
 # --- Streamlit UI ---
 st.set_page_config(page_title="🧠 Deep Research Assistant 3.0", layout="centered")