Selecting certain GameObjects messes up their lightmap

Exactly as title says, I recorded a GIF to better show this:



If the GIF doesn't show up: https://ibb.co/jU8wVd
Basically as soon as I select a lightmapped object, the lightmap on it acts like the UVs are wrong, or like the object has the wrong lightmap. Reloading the scene reverts everything to normal.

I don't have any clue on how to reproduce this. We recently baked this scene on the same machine where this problem shows up, but we didn't touch it again since. This happened on another scene too some time ago. We are using Unity 2017.4.3f1 but I recall we had the same issue with previous minor versions.