It's happened to me multiple times. Was fine but then days/a week ago started happening - not sure of time frame.
In case it matters, I'm playing on a Mac.
As a test I created a quick game using only Core, no mods. Used dev mode to create three colonists with 20 construction and creativity inspiration. Set them to each construct a sarcophagus. All three caused the error.
You can find the saves (pre-error named Test1, post-error named Test2) and the debug log showing the error (debug.txt) at:
https://drive.google.com/file/d/1kRMKeVZGnYSqbM7UzKuD1u0Z0_2HzQwy/view?usp=sharing, https://drive.google.com/file/d/1vtUb9TVX82JIWiZHS9QsR9v-R2AV7drZ/view?usp=sharing, https://drive.google.com/file/d/1ybjFD1Cx4VN_my0_qk14EZc6pZK8-MqI/view?usp=sharing
Also, confirmed that the issue is not happening for items that only have an Art tab (no Storage/Content) such as furniture such as Dressers and weapons such as Maces when they are Excellent and above quality. In fact, I think it may be a problem with the Storage tab - was that a recent addition? It's in the same location as the Art tab on my older sacophagi... Oddly, Excellent sarcaphogi get created but no Art tab appears but Legendary and Masterwork sarcophagi just cause the error and disappear. Do Excellent saraphogi no longer get Art?
In case it matters, I'm playing on a Mac.
As a test I created a quick game using only Core, no mods. Used dev mode to create three colonists with 20 construction and creativity inspiration. Set them to each construct a sarcophagus. All three caused the error.
You can find the saves (pre-error named Test1, post-error named Test2) and the debug log showing the error (debug.txt) at:
https://drive.google.com/file/d/1kRMKeVZGnYSqbM7UzKuD1u0Z0_2HzQwy/view?usp=sharing, https://drive.google.com/file/d/1vtUb9TVX82JIWiZHS9QsR9v-R2AV7drZ/view?usp=sharing, https://drive.google.com/file/d/1ybjFD1Cx4VN_my0_qk14EZc6pZK8-MqI/view?usp=sharing
Also, confirmed that the issue is not happening for items that only have an Art tab (no Storage/Content) such as furniture such as Dressers and weapons such as Maces when they are Excellent and above quality. In fact, I think it may be a problem with the Storage tab - was that a recent addition? It's in the same location as the Art tab on my older sacophagi... Oddly, Excellent sarcaphogi get created but no Art tab appears but Legendary and Masterwork sarcophagi just cause the error and disappear. Do Excellent saraphogi no longer get Art?