Home Assistant, ESPHome, and Unexpected Changes

I have been using esphome with various m5stack controllers with home assistant for collecting environment data in my apartment.
Being able to write a bit of yaml and have a fairly functional sensor is great.

I have been using the picture element card with some state badges to have a nice overview of my apartment and it has generally worked well.
I noticed however with a recent update, that all of the badges had a much longer label and needed to look into what changed.

It seems like there was a legacy format exception that was removed and released in 2025.5, though one has to look at the detailed changelog to find a reference of it.
So now that I actually understand the bug, I need to fix my ESPHome configs.

Initially, I started with a single node and updated it, however this resulted in all entities for that component receiving a new id, therefore losing any historical data for that entity. After messing up on a second sensor, I was able to figure out a rough way to fix things in a way that kept old data.

Given an entity with ID old_friendly_name_<entity>, I manually updated it to new_device_name_<entity> in the Home Assistant UI before deploying a new ESPHome build to the device. Verifying that this worked, I then went one device at a time, fixing the metrics in Home Assistant and then rebuilding and deploying the new ESPHome device config.

Once I verified that each device was correct, I then needed to go around various dashboards and update the entity references there.
This did make me long for a way to manage dashboard yaml files in git though I was not able to find good documentation on that during my search.

I do not necessarily fault the Home Assistant developers or ESPHome developers.
Keeping around legacy code does have a cost, and many of the developers are working on things in their free time and not getting paid.
I am sure it is very likely when I first configured things, I copied an example I found on the internet, unaware that it was not the recommended way to use friendly name, and then likely kept propagating things.

I do however wish there was a more visible callout in the changelog, considering the quote I found in the issue.

I think a few folks might be a bit frustrated with this change, especially if they’ve been stuck with some odd naming from before we had friendly names. There might be a little transition pain, but once everything’s consistent, it’ll be way easier to understand and keep things tidy moving forward.

That is part of the nature of open source however.