it's similar to changelog requirement in GPL but unlike GPL this should be accessible and visible to the end use (not just the developers in the changelog that is hidden from binary end users) this can be done in “about” menu or in splash screens or package name or in any suitable mean as long as there is no confusion to a common user.
or make your software proprietary we don't care”
in case you are going to ask me how do you define useful and harmful it's out of the scope of waqf we are not going to judge and as you know, the Fiqh (Islamic jurisprudence) is well-established and courts can judge if this or that is considered a useful and Waqf-able or not.
Due to Islamophobia syndrome we expect that Waqf won't be treated fairly in the west. And here are some answers to some expected questions.