Improved and updated version here by GonzoInc1 https://www.curseforge.com/wow/addons/out-of-mana-2
Description
Automatically send a chat message (works on instances) and say /oom (emote and voice, works everywere) to warn your party members when reaching a certain mana percentage (can be changed via slash commands).
Use
Useful for healers to warn tanks and even to yourself when you don't notice that are running out of mana! :)
Slash Commands
Type "/mana" in chat to see the current mana limit when the alert activates.
Type "/mana x" to change the current limit percentage, "x" is a number. (/mana 30 to send the alert when 30% mana and so on...).
Please, if you have any suggestions or problems, let me know! :D