Make Ikea block candle smart

Hello everyone,
I was unfortunately unable to finish reading an article because it was behind a paywall.
It described how someone made a standard LED block candle Zigbee-enabled using a Zigbee module from a light bulb and controlled it via Home Assistant.
I find the whole thing very, very interesting.
Has anyone ever done this before?

As that topic is really a hardware development question and not a Zigbee end-user help/support question (which is “configuration” section is about) you will probably be much better of asking that question in either the Hardware section of this forum and/or probably better post the same question in the Zigbee2MQTT discussion sections on GitHub:

PS: Regardless, please do post a link here for reference if you post this question somewhere else too.