Headcanon
✴ Before her marriage to Odin was arranged, Frigga had already visited each of the Nine Realms and the roots of Yggdrasil in an endless quest for knowledge. She learned the art of metalworking on Svartálfaheimr, medicine (and dancing) in Álfheimr, spell-songs on Vanaheimr, traveling with light on Muspellsheimr, illusions in Niflheimr, shape-changing on Jotunheimr, mercy in Helheimr, and the simple joy of living in the present on Midgardr.
✴ She has a gift for prophecy, but either cannot or will not share what she sees.
✴ Frigga taught Loki nearly everything he knows about magic.
✴ She made the helmets. Both of them.
✴ If given the chance, she'll mother anyone and everyone she meets.
✴ When the All-Father fell into the Odinsleep in the past, Frigga took on the duties of the King until he woke again.
✴ When Odin returned from Jotunheim with one eye and a child that wasn't his, she chose to see to the child while others tended to the king.
✴ Frigga was the one who decided they would raise the child as their own.
✴ When she learned that Odin would keep the secret of Loki's birthright even from Loki himself, she was given the choice of silence or Loki's fate changed from that of a prince to that of being raised a prisoner, a hostage of Jotunheim in Asgard. She chose silence.
✴ The fight that arose when Odin delivered her the news of her second son's fall from the Bifrost raged for a night and a day, and Frigga has not spoken privately to Odin since.
✴ The Queen of Asgard is secretly a tomboy who would rather be running around in the gardens or hunting on horseback during long, boring afternoons.