I'm trying to get the intro to a list of Wikipedia pages using the "extracts" property with "exintro=True". This works fine for most sites, but for a few of them the API returns an empty extract field. See for example:

When looking at the page "https://en.wikipedia.org/wiki/Anthem" there definitely seems to be text before the first section, so I think I should be getting something. Indeed without the "exintro" parameter, I get the expected return.

Any idea why this occurs?

Best,

Bertel