XLM-RoBERTa tokenizer changes characters during tokenization
I'm using `transformers` 3.5.0.

Whenever the XLM-RoBERTa tokenizer encounters some characters such as '²' (super-script 2, `ord('²')` is 178), it converts them to other characters (in this example, to the plain '2', with `ord('2')` being 50).

That is, with `tokenizer = AutoTokenizer.from_pretrained('xlm-roberta-large')`, `tokenizer.tokenize('²')` or, altnernatively, `tokenizer.tokenize(chr(178))` returns `['▁2']`.

Hi, this is unfortunately a limit of this tokenizer. We try to stay as close as possible to the original implementation, so we will not be able to change this behavior.<|||||>I see. Well, it's not a big deal, as the characters it replaces are quite rare and not really important, at least not for my application. So, I just replace them upfront in the text to make sure that the output of the tokenizer still matches the input.

Thanks for the awesome work you are doing by providing this and other libraries!<|||||>Glad you like it :)