Fresh installation and directly errors in the log

Hello,
I completely reset my Home Assistant system at the weekend.
In order to find as many errors as possible, I have not integrated any devices for the first time.
Currently, I have only set up the connection to the Home Assistant Cloud (NabuCasa) in my HA system and installed HACS.
Nevertheless, I already have several errors in my log.

The following messages do not always appear, but sometimes.
And above all, I have no idea where these webhooks are coming from.
Can anyone tell me what I can do about it?

2021-10-12 13:44:42 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 2b0294bc464bff945cc3d13279044a4e8a3196a729abddd7ed2065dbb00e9d8c from cloud
2021-10-12 13:44:46 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 2b0294bc464bff945cc3d13279044a4e8a3196a729abddd7ed2065dbb00e9d8c from cloud
2021-10-12 13:44:50 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 2b0294bc464bff945cc3d13279044a4e8a3196a729abddd7ed2065dbb00e9d8c from cloud
2021-10-12 13:45:21 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 2b0294bc464bff945cc3d13279044a4e8a3196a729abddd7ed2065dbb00e9d8c from cloud

The next error appears every time I restart.
It seems to be about the connection to the Home Assistant Cloud, but what the error wants to tell me - no idea.
And again, I have no idea how to solve the problem.
Does anyone have any advice?

2021-10-12 13:48:49 ERROR (MainThread) [snitun.client.client_peer] Challenge/Response error with SniTun server (0 bytes read on a total of 32 expected bytes)
2021-10-12 13:48:49 ERROR (MainThread) [hass_nabucasa.remote] Connection problem to snitun server

I know that you won’t get rid of all error messages, in an HA installation there will always be errors in the log.
But, I would like to have an error-free(!) HA system at least in the beginning.
Even the warnings are extremely annoying.
And changing the log settings so that they are no longer displayed is no solution either.
This only hides the problems, but I would like to solve them.

The SniTun error is a known issue and being discussed on github.