Ruling On To Hide The Body Shape?
In light of the details, it is clear that hiding knees and shoulders are better, not obligatory in the typical sense of the word, but it is not allowed as a preemptive measure. However, culturally and naturally, women are supposed to wear dresses that are more covering. One should not go near the borderline, otherwise, the next step will most likely be in the prohibited area.
So it’s their opinion rather than the order of religion