AttributeError: 'str' object has no attribute 'decode'

I’m running Home Assistant (version 2021.1.1) on Clear Linux. After one of the latest updates, I’m no longer able to login to the web interface. The follow error shows in the log for every login attempt:

2021-01-13 18:39:23 ERROR (MainThread) [aiohttp.server] Error handling request
Traceback (most recent call last):
  File "/usr/lib/python3.9/site-packages/aiohttp/web_protocol.py", line 422, in _handle_request
    resp = await self._request_handler(request)
  File "/usr/lib/python3.9/site-packages/aiohttp/web_app.py", line 499, in _handle
    resp = await handler(request)
  File "/usr/lib/python3.9/site-packages/aiohttp/web_middlewares.py", line 118, in impl
    return await handler(request)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/http/request_context.py", line 18, in request_context_middleware
    return await handler(request)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/http/ban.py", line 72, in ban_middleware
    return await handler(request)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/http/auth.py", line 127, in auth_middleware
    return await handler(request)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/http/view.py", line 129, in handle
    result = await result
  File "/usr/lib/python3.9/site-packages/homeassistant/components/http/ban.py", line 83, in handle_req
    resp = await func(view, request, *args, **kwargs)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/auth/__init__.py", line 251, in post
    return await self._async_handle_auth_code(hass, data, request.remote)
  File "/usr/lib/python3.9/site-packages/homeassistant/components/auth/__init__.py", line 314, in _async_handle_auth_code
    access_token = hass.auth.async_create_access_token(refresh_token, remote_addr)
  File "/usr/lib/python3.9/site-packages/homeassistant/auth/__init__.py", line 446, in async_create_access_token
    return jwt.encode(
AttributeError: 'str' object has no attribute 'decode'

I have posted the issue on github: