Is it permissible to work in a hair salon that offers its services to non-Muslim women with the intention of dawah (inviting others to Islam), knowing that the majority of customers will not be Muslim women wearing hijab?

A woman's work as a hairdresser for women is permissible in principle, as long as it is not associated with forbidden acts. However, if the majority of people in the area are non-Muslims, then working in this field is not permissible, because it is considered assisting them in abandoning the hijab, displaying themselves immodestly (tabarruj), and altering Allah's creation. This contradicts Allah's saying: (And cooperate in righteousness and piety, but do not cooperate in sin and aggression). The benefit of inviting non-Muslim women to Islam does not permit participating with them in sins or assisting them in them. The benefit of da'wah (inviting to Islam) must be achieved through other means that do not involve committing forbidden acts.