Is it better to be in the mosque or at home to supplicate an hour before Maghrib in Ramadan, a time when it is said that supplications are answered?

There is no evidence specifying a particular hour before Maghrib for prayers to be answered in Ramadan (definition); rather, the fasting person's supplication is answered at the time of breaking fast. It is recommended for the fasting person to supplicate throughout their fast, from the beginning of the day until its end, due to the Prophet, peace and blessings be upon him, saying: "Three whose supplication is not rejected: a fasting person until he breaks his fast, a just ruler, and an oppressed person."