Johnston's first involvement in the series was as the lead vocalist for the scrapped My Little Pony Equestria Girls song My Little Pony Friends. She later lent her voice to Tricks Up My Sleeve and Life is a Runway for Rainbow Rocks. In Friendship Games, Johnston sang backup for the title track, CHS Rally Song, ACADECA, and Unleash the Magic. In other My Little Pony work, she sang backup for True True Friend Winter Wrap-Up. Johnston released her self-titled debut album in June 2016.