I think it would have been while you were rebuilding - it works perfectly now. 
Safe mode is really useful for checking if any custom themes or plugins are the cause of anything, and can often give you a hint as to what might be the issue.
Though in this case I don’t think it would have helped. 
As @Falco identified, it seems you got some corrupted assets during your first rebuild and needed to do another. I’m glad it’s up and running now though.