Lots of weird stuff happens if you have the In the Shadows (Umbral Choir) gameplay affinity plus Riftborn visual affinity -


You can only produce one pop per turn for your entire empire.


If you have a sanctuary link set or a non-full home system, queuing multiple pops has one finish production, and all the rest get to 99% completion but not actually be produced.


If you don't have a sanctuary link set and your home system is not full it gets even weirder. All the ordered pops are produced (cleared from the list and the governor gets xp for them), but then they just disappear into oblivion. They don't get sent to any sanctuary, they just seem to be destroyed on production.