diff --git a/ipykernel/debugger.py b/ipykernel/debugger.py
index 224678232..2ba6bc7c7 100644
--- a/ipykernel/debugger.py
+++ b/ipykernel/debugger.py
@@ -18,6 +18,8 @@
 from .compiler import get_file_name, get_tmp_directory, get_tmp_hash_seed
 
 try:
+    if "PYDEVD_IPYTHON_COMPATIBLE_DEBUGGING" not in os.environ:
+        os.environ["PYDEVD_IPYTHON_COMPATIBLE_DEBUGGING"] = "1"
     # This import is required to have the next ones working...
     from debugpy.server import api  # noqa