Using this method, I was expecting being able to write long lines of text in my lang file and let this method handle the page wraps, but instead I get this result:

The code for this particular entry is :

List<IPage> explosionFurnace = new ArrayList<>();
explosionFurnace.addAll(PageHelper.pagesForLongText(prefix("explosionfurnace.content")));
entries.put(new ResourceLocation(prefix("explosionfurnace")), new Entry(explosionFurnace, prefix("explosionfurnace")));

Well... yeah? You're supposed to pass your localized string. Hence why the param is called locText.