Kernel error: ipykernel AssertionError while running notebook from conda

Question

Error

Traceback (most recent call last):
  File "G:\anaconda\envs\tf\lib\runpy.py", line 192, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "G:\anaconda\envs\tf\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\sk_np\AppData\Roaming\Python\Python38\site-packages\ipykernel_launcher.py", line 16, in <module>
    app.launch_new_instance()
  File "G:\anaconda\envs\tf\lib\site-packages\traitlets\config\application.py", line 845, in launch_instance
    app.start()
  File "C:\Users\sk_np\AppData\Roaming\Python\Python38\site-packages\ipykernel\kernelapp.py", line 477, in start
    ioloop.IOLoop.instance().start()
  File "G:\anaconda\envs\tf\lib\site-packages\tornado\platform\asyncio.py", line 199, in start
    self.asyncio_loop.run_forever()
  File "G:\anaconda\envs\tf\lib\asyncio\windows_events.py", line 314, in run_forever
    assert self._self_reading_future is None
AssertionError

System Information:

• conda 4.10.3
• python 3.8
• Running on windows system

Package versions:

• jupyter_client==6.1.7
• ipython==7.18.1
• ipykernel==5.3.4

Steps to reproduce:

• conda create -n tf python==3.8
• conda activate tf
• pip install jupyter_http_over_ws
• jupyter notebook

Relate question: Similar error but unrelated issue