Libram Reminder that shows the currently equipped Libram in an Icon (Holy Shield icon for Repentance, SoR icon for Divine Purpose and Consecration icon for Eternal Rest)
Also shows a glowing icon reminder next to it during boss encounters if you don't have Libram of Divine Purpose equipped (for Illidan and Mother Shahraz it reminds for Libram of Repentance instead and for Shade of Akama and Jan'alai it shows for Eternal Rest instead). Encounter glowing reminders can be adjusted in Load settings.