fiqhsalatnawafilraghibarawatib
Ibn Abi Zayd mentions: two rakats of fajr after dawn and before Subh, with the Fatiha silently; four rakats after Dhuhr in pairs, the same before Asr; two after Maghrib (more is good, six is fine); and voluntary prayer between Maghrib and Isha is encouraged. These are recommended, not obligatory.