Thank you! I have thought about initializing the new embeddings based on equivalent tokens in the old ones (e.g. by translating a token to English and finding the closest old token), but this is all getting convoluted.

New tokenizer and embeddings will probably be required anyway, since the language is practically missing from any model worth to play with, but at that point simply creating a small specialized model from scratch is perhaps a better bet than trying to glue it upon a big ready model?