Multiple input_number config files?

Looking at the guide to split the configuration file it states that multiple files can be imported for the same integration if different labels are used. This seems to work for light and some other ones but not input_number.

When I try to include a configuration file with the row below and check if the configuration is valid I get the error underneath. I have tested different labels to see if there are some reserved keywords and this is for now the only place where I include a configuration for or configures input_numbers in yaml. Is this a bug or am I missing something?
If I remove the label the file imports correctly.

input_number lights: !include autolight/light_input_number.yaml
2021-08-13 23:36:09 ERROR (MainThread) [aiohttp.server] Error handling request
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/aiohttp/", line 422, in _handle_request
    resp = await self._request_handler(request)
  File "/usr/local/lib/python3.9/site-packages/aiohttp/", line 499, in _handle
    resp = await handler(request)
  File "/usr/local/lib/python3.9/site-packages/aiohttp/", line 119, in impl
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 60, in security_filter_middleware
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 206, in forwarded_middleware
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 24, in request_context_middleware
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 78, in ban_middleware
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 144, in auth_middleware
    return await handler(request)
  File "/usr/src/homeassistant/homeassistant/components/http/", line 135, in handle
    result = await result
  File "/usr/src/homeassistant/homeassistant/components/config/", line 29, in post
    errors = await async_check_ha_config_file(["hass"])
  File "/usr/src/homeassistant/homeassistant/", line 923, in async_check_ha_config_file
    res = await check_config.async_check_ha_config_file(hass)
  File "/usr/src/homeassistant/homeassistant/helpers/", line 178, in async_check_ha_config_file
    result[domain] = config[domain]
KeyError: 'input_number'

cant have that format

here a screen shot of mine

note the i!include_dir_merge_list will load all yaml file in said folder

Ok. But why does not input_select handle the label in the same way as automation? Where can I see which integrations that handle labels and multiple imports from named files?