Websocket errors ... may be related to backup

This happens only once a day and strictly immediately after the backup is completed.
This was in versions 2024.02.x, 2024.03.x and continues in 2024.04.01.
There is no supervisor reboot or any other “bad” consequences, only these “websocket” errors.

What could it be?
Does anyone have any thoughts on the topic?

Supervisor log:

2024-04-05 01:08:07.021 INFO (MainThread) [supervisor.backups.manager] Creating partial backup with slug 27a00dd7 completed
2024-04-05 01:08:07.036 WARNING (MainThread) [supervisor.homeassistant.websocket] Connection is closed
2024-04-05 01:08:07.039 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042418' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.041 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042419' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.042 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042420' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.045 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042421' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.046 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042422' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.048 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042423' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.049 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042424' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.050 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042425' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.052 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042426' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.053 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042427' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.054 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042428' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.055 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042429' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.057 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042430' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.058 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042431' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.059 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042433' coro=<HomeAssistantWebSocket.async_supervisor_update_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:283> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 290, in async_supervisor_update_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'
2024-04-05 01:08:07.059 ERROR (MainThread) [asyncio] Task exception was never retrieved
future: <Task finished name='Task-5042434' coro=<HomeAssistantWebSocket.async_supervisor_event() done, defined at /usr/src/supervisor/supervisor/homeassistant/websocket.py:321> exception=AttributeError("'NoneType' object has no attribute 'close'")>
Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 266, in async_send_message
await self._client.async_send_command(message)
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 94, in async_send_command
return await self._futures[message["id"]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
supervisor.exceptions.HomeAssistantWSConnectionError: Connection was closed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 326, in async_supervisor_event
await self.async_send_message(
File "/usr/src/supervisor/supervisor/homeassistant/websocket.py", line 268, in async_send_message
await self._client.close()
^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'close'

System information

Version core-2024.4.1
Installation Type Home Assistant OS
Development false
Supervisor true
Docker true
User root
Virtual Environment false
Python Version 3.12.2
Operating System Family Linux
Operating System Version 6.6.20-haos
CPU Architecture x86_64|