A Wonder Bug?

[Santa Klaus]

I'm in the prehistoric era and have the option to build Lascaux Paints wonder. At the very next turn, the option is gone. What Happened?!?
I'm attaching screenshots of the two consecutive turns

 

[raxo2222]

Someone built it before you, or you lost requirements for it.

 

[Santa Klaus]

I checked in world builder and no other civ has built it. I still meet all the requirements for Lascaux, i.e. cave paintings and caves in city vicinity.
I noticed that at the end of turn of that safe a civic had been built: Burn Trash.
I reloaded that safe and let it finish its turn and on the next turn Lascaux was back as a build option. So now I have same-turn safes with Lascaux and without. I guess it glitched...

 

[raxo2222]

You can upload save so we can reproduce it - this may be some deeper code problem.

 

[Santa Klaus]

Never mind, turns out it was all self-inflicted, I had removed the cave feature by accident with the world builder. And that removed a basic requirement. Duh!

PS, I'll stop posting and waste your time...