When trying to translate Auri (band) from English to Portuguese, adding all paragraphs and sections (except for the infobox, which seems to have a different issue, probably T207449) results in an empty paragraph and the "Automatic translation failed" message showing:
Inspecting the console and the network tabs, it seems that the translation service (Yandex in this case) was able to return the translation, but "Cannot read property 'start' of null" error was getting in the way somehow: