If it counts, I encountered a Java file that, unbeknownst to me at the time, was duplicated across two different places. The project was essentially abandoned for years, and the file was one that didn’t change much so I left it alone for a year or so.
Eventually I had to add a method to it. Compiled just fine, runtime threw a no such method error. Turned out Eclipse was using one, but when Maven did its build it used the old duplicate I didn’t know existed.
Took me a while to find that one!
I mean, it does look nice, but to be honest I think you could’ve gotten Ikea’s lights with the ZigBee-enabled controller (plus a dongle for your Home Assistant hardware if you don’t already have one) and used that. I did that, used a Home Assistant automation to match the brightness with another dimmable wall-controlled accent light in the kitchen (both of which I usually prefer full brightness on anyway) and it’s worked great so far.