diff --git a/jupyter_server/base/handlers.py b/jupyter_server/base/handlers.py
index e6e6b3246e..b1b783cca9 100644
--- a/jupyter_server/base/handlers.py
+++ b/jupyter_server/base/handlers.py
@@ -10,7 +10,6 @@
 import mimetypes
 import os
 import re
-import traceback
 import types
 import warnings
 from http.client import responses
@@ -748,7 +747,9 @@ def write_error(self, status_code: int, **kwargs: Any) -> None:
             else:
                 reply["message"] = "Unhandled error"
                 reply["reason"] = None
-                reply["traceback"] = "".join(traceback.format_exception(*exc_info))
+                # backward-compatibility: traceback field is present,
+                # but always empty
+                reply["traceback"] = ""
         self.log.warning("wrote error: %r", reply["message"], exc_info=True)
         self.finish(json.dumps(reply))
 
diff --git a/jupyter_server/services/kernels/handlers.py b/jupyter_server/services/kernels/handlers.py
index 2fb753e93c..217f0c9cc2 100644
--- a/jupyter_server/services/kernels/handlers.py
+++ b/jupyter_server/services/kernels/handlers.py
@@ -5,7 +5,6 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 import json
-from traceback import format_tb
 
 try:
     from jupyter_client.jsonutil import json_default
@@ -102,8 +101,7 @@ async def post(self, kernel_id, action):
             except Exception as e:
                 message = "Exception restarting kernel"
                 self.log.error(message, exc_info=True)
-                traceback = format_tb(e.__traceback__)
-                self.write(json.dumps({"message": message, "traceback": traceback}))
+                self.write(json.dumps({"message": message, "traceback": ""}))
                 self.set_status(500)
             else:
                 model = await ensure_async(km.kernel_model(kernel_id))