Error when input text contains an empty line

[dlippold]

I have installed OPUS-MT on Ubuntu 22.04 as described on the project page (manual setup). I can translate some text by using the web site localhost:8888, for example from English to German. But when the input text contains an empty line I get the following error output an no text is translated:

Uncaught exception POST /api/translate (127.0.0.1)
HTTPServerRequest(protocol='http', host='localhost:8888', method='POST', uri='/api/translate', version='HTTP/1.1', remote_ip='127.0.0.1')
Traceback (most recent call last):
File "/home/opusmt/.local/lib/python3.10/site-packages/tornado/web.py", line 1784, in _execute
result = method(*self.path_args, **self.path_kwargs)
File "/home/opusmt/Opus-MT/server.py", line 124, in post
translation = self.worker.translate(self.args['source'])
File "/home/opusmt/Opus-MT/server.py", line 30, in translate
sentences = self.contentprocessor.preprocess(text)
File "/home/opusmt/Opus-MT/content_processor.py", line 47, in preprocess
normalized_text = '\n'.join(self.normalizer(line) for line in srctxt.split('\n')) # normalizer do not accept '\n'
TypeError: sequence item 2: expected str instance, list found
500 POST /api/translate (127.0.0.1) 20.03ms

Is there a possibility to translate text with empty lines?