Magento 2: Translate This is a required field

I’m already having a lot of trouble translating some Magento 2 texts, but I really can’t seem figure this one out. I’m trying to translate the “This is a required field.” text to Dutch. I already tried editing it in my nl_NL.csv, in which other texts are being translated as well. I deployed, cleared my cache, removed my pub/static folder, all of which do not give me a result.

How do I do this?

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