WTH this weird error when I set friendly_name in Customizations?

Not sure if this is the right place for this, but I’ve spotted it a few times and never though it worth posting as a bug as it doesn’t actually stop anything from working. But, whever I use Configuration > Customizations to add a friendly name to an entity which doesn’t have one by doing the following:

  • Select entity from list
  • Select Other from pick an attribute to override
  • Enter friendly_name as the attribute name and the friendly name as the value

This error appears:

The friendly name does get set successfully and, after reloading the page, the error goes away. So it only appears to be an issue when adding a friendly name to an entity without one. The friendly name can be updated without the error message and other attributes can be added with this error.

I wonder if it is something to do with the list of entities being displayed based on their friendly names and adding a friendly name after the list was populated is somehow confusing it?

Edit: And customize.yaml is defintely included properly (this error doesn’t display until I add the friendly name)

homeassistant:
  ...other stuff...
  customize: !include customize.yaml