Home Assistant release with the issue:
0.71.0

Last working Home Assistant release (if known):
Unknown

Operating environment (Hass.io/Docker/Windows/etc.):
I am using home assistant as a docker within unRAID
https://hub.docker.com/r/homeassistant/home-assistant/

Component/platform:
IKEA Tradfri (Tradfri)
https://www.home-assistant.io/components/tradfri/

Description of problem:
Using "discovery:" in my config.yaml, HA finds the Tradfri gateway when it is plugged in, and prompts for configuration. Clicking configuration prompts for security code, which I provide. The panel then disappears and the following error shows up in the log:

2018-06-16 00:55:13 ERROR (MainThread) [homeassistant.core] Error doing job: Task exception was never retrieved
Traceback (most recent call last):
  File "/usr/src/app/homeassistant/helpers/entity_platform.py", line 219, in async_add_entities
    await asyncio.wait(tasks, loop=self.hass.loop)
  File "/usr/local/lib/python3.6/asyncio/tasks.py", line 304, in wait
    raise ValueError('Set of coroutines/Futures is empty.')
ValueError: Set of coroutines/Futures is empty.
2018-06-16 06:30:01 ERROR (SyncWorker_17) [homeassistant.core] Error doing job: Task was destroyed but it is pending!

The Tradfri gateway and/or associated devices never show up in the HA interface after initial configuration.

Problem-relevant configuration.yaml entries and (fill out even if it seems unimportant):

# Discover some devices automatically
discovery:

I have also tried with the following with the same result:

# Tradfri
tradfri:
  host: 192.168.1.132

Traceback (if applicable):

Additional information:
I have tried resetting the Tradfri hub by holding the reset pin until the lights blink in unison, but received the same error after this attempt.

This error may be related to this open issue: #9822
But that issue seemed to relate to an upgrade of Home Assistant, and seems to involve the relevant component functioning for a period before failing, as opposed to never working to start with.
(So I do not believe this issue to be a duplicate.)
I did not find any solutions there to try.