When I added the Philipps Hue integration, HA duplicated a couple of entities with its internal Light integration. These are not needed and I would like to remove them as they just cause confusion. In the entity list they are read-only, (so not selectable, etc.) do not have a unique ID, are not in the .storage/core.entity_registry file (or .storage/lovelace) …
I have a similar issue. I once tried out the opnsense integration and it generated for every device in my network a tracker entity. I disabled it again, but I cannot remove the dead entities. Also, when I go to dev → states and the (i) symbol, there is no remove button.
I came here because I was having the exact same issue, the Hue integration had created entities for a zone I then deleted from the Hue App, but the entities persisted in Home Assistant (and obviously didn’t function anymore). The issue turned out to be that the Home Assistant app was caching the old entities, the Hue integration had actually deleted them. Closing the app on my android phone and starting it up again cleared them out. What clued me in was that I opened the core.entity_registry file on my computer and could not find the dummy entities to save my life. You may also need to delete the Hue integration and then restart HA, at least I did, not sure if that was a necessary step or not. At any rate, I hope this helps the next poor sap who runs into this.
I know this thread has been dead for like 18 months, but its one of the first ones to come up on Google. Something else to take note of is that the presence and history of entities can be cached in the browser.
If you’ve removed the integration, removed the yaml, or however they were created in the first place - try clearing your browser cache. There is a fair chance that after a restart to completely delete the actual entity, and then clearing the cache to remove them from the browser storage, that they’ll finally disappear from the UI.