Thanks, Tom! Your answer brought me one step further: although I had already tried the /config-cleanout myself, this time I did it after stopping the core, which brought me a seemingly virgin version.
But alas, it didn’t bring me the Hue integration; same problem: HA doesn’t find the Hue bridge and, after submission of the hue linking request, it’s the “unknown error” response again.
However, I found some errors (see below) in the logfile.
One thing that strikes me is that the Supervisor (how do I get to that thing?) uses an odd IP-address (172.30.32.2), usually assigned to devices/processes that did not receive or obtain a proper one…
THE LOGFILE
2022-10-16 23:41:07.622 WARNING (MainThread) [homeassistant.components.http.ban] Login attempt or request with invalid authentication from supervisor (172.30.32.2). Requested URL: ‘/api/config’. (HomeAssistantSupervisor/2022.10.0 aiohttp/3.8.3 Python/3.10)
2022-10-16 23:41:23.613 ERROR (MainThread) [homeassistant.components.homeassistant_alerts] timeout fetching homeassistant_alerts data
2022-10-16 23:43:35.101 ERROR (MainThread) [frontend.js.latest.202210100] :0:0 Script error.
2022-10-16 23:46:21.255 ERROR (MainThread) [aiohttp.server] Error handling request
Traceback (most recent call last):
File “/usr/local/lib/python3.10/site-packages/aiohttp/web_protocol.py”, line 435, in _handle_request
resp = await request_handler(request)
File “/usr/local/lib/python3.10/site-packages/aiohttp/web_app.py”, line 504, in _handle
resp = await handler(request)
File “/usr/local/lib/python3.10/site-packages/aiohttp/web_middlewares.py”, line 117, in impl
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/security_filter.py”, line 60, in security_filter_middleware
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/forwarded.py”, line 100, in forwarded_middleware
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/request_context.py”, line 28, in request_context_middleware
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/ban.py”, line 82, in ban_middleware
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/auth.py”, line 236, in auth_middleware
return await handler(request)
File “/usr/src/homeassistant/homeassistant/components/http/view.py”, line 136, in handle
result = await result
File “/usr/src/homeassistant/homeassistant/components/config/config_entries.py”, line 180, in post
return await super().post(request, flow_id)
File “/usr/src/homeassistant/homeassistant/components/http/data_validator.py”, line 73, in wrapper
result = await method(view, request, data, *args, **kwargs)
File “/usr/src/homeassistant/homeassistant/helpers/data_entry_flow.py”, line 110, in post
result = await self._flow_mgr.async_configure(flow_id, data)
File “/usr/src/homeassistant/homeassistant/data_entry_flow.py”, line 280, in async_configure
result = await self._async_handle_step(
File “/usr/src/homeassistant/homeassistant/data_entry_flow.py”, line 367, in _async_handle_step
result: FlowResult = await getattr(flow, method)(user_input)
File “/usr/src/homeassistant/homeassistant/components/hue/config_flow.py”, line 163, in async_step_link assert bridge is not None
AssertionError