What is making this notification that pops up for addons?
 

edit: Thanks for the responses. It was the toast notifications coming from these 2 addons.

Screenshot 1: http://imgur.com/BfBeIfx
Screenshot 2: http://imgur.com/dvhfz31

The addon I'm looking to be identified is the one shown in the bottom right of the screen in those screenshots.


List of everything enabled:

_NPCScan
_NPCScan.Overlay
Altoholic
Altoholic_Achievements
Altoholic_Agenda
Altoholic_Characters
Altoholic_Grids
Altoholic_Guild
Altoholic_Search
Altoholic_Summary
Archy
AtlasLoot
AtlasLoot_BurningCrusade
AtlasLoot_Cataclysm
AtlasLoot_ClassicWoW
AtlasLoot_Crafting
AtlasLoot_Loader
AtlasLoot_MistsofPandaria
AtlasLoot_WorldEvents
AtlasLoot_WrathoftheLichKing
Auc-Advanced
Auc-Filter-Basic
Auc-ScanData
Auc-Stat-Histogram
Auc-Stat-iLevel
Auc-Stat-Purchased
Auc-Stat-Simple
Auc-Stat-StdDev
Auc-Util-FixAH
BeanCounter
DataStore
DataStore_Achievements
DataStore_Agenda
DataStore_Auctions
DataStore_Characters
DataStore_Containers
DataStore_Crafts
DataStore_Currencies
DataStore_Inventory
DataStore_Mails
DataStore_Pets
DataStore_Quests
DataStore_Reputations
DataStore_Spells
DataStore_Stats
DataStore_Talents
Enchantrix
Enchantrix-Barker
Grail
Grail-Achievements
Grail-Reputations
Grail-When
Informant
Loremaster
MBB
MogIt
MogIt_Accessories
MogIt_Cloth
MogIt_Leather
MogIt_Mail
MogIt_OneHanded
MogIt_Other
MogIt_Plate
MogIt_Ranged
MogIt_TwoHanded
Overachiever
Overachiever_Tabs
Overachiever_Trade
PetTracker
PetTracker_Breeds
PetTracker_Config
PetTracker_Journal
PetTracker_Switcher
PetTracker_Upgrades
Profession_Assistance
Skada
SlideBar
Spy
Stubby
!Swatter
ElvUI_Config
ElvUI
DBM-StatusBarTimers
DBM-Core
DBM-DefaultSkin
DBM-GUI
DBM-BaradinHold
DBM-BastionTwilight
DBM-BlackTemple
DBM-BlackwingDescent
DBM-BWL
DBM-Brawlers
DBM-ChamberOfAspects
DBM-Coliseum
DBM-DMF
DBM-DragonSoul
DBM-EyeOfEternity
DBM-Firelands
DBM-HeartofFear
DBM-Icecrown
DBM-Karazhan
DBM-MogushanVaults
DBM-MC
DBM-Hyjal
DBM-Naxx
DBM-Onyxia
DBM-Outlands
DBM-Pandaria
DBM-Party-BC
DBM-Party-Cataclysm
DBM-Party-MoP
DBM-Party-WotLK
DBM-AQ20
DBM-Scenario-MoP
DBM-Serpentshrine
DBM-SiegeOfOrgrimmar
DBM-Sunwell
DBM-AQ40
DBM-TerraceofEndlessSpring
DBM-TheEye
DBM-ThroneFourWinds
DBM-ThroneofThunder
DBM-Ulduar
DBM-VoA
DBM-WorldEvents

Archy - it says that on top of the frame

Look at the second screenshot. I just disabled archy and it isn't that one.

edit: It looks like any addon that has toast notifications does this. I have the battlenet message frame which I thought was the one that controlled the toasts moved up to the top of the screen which is where the confusion came from. I guess I'll look into that.

NPCScan?

You have two different things in the bottom right of your two screenshots.

xD

It says on the screenshot, the name of the addon making these - NPCScan

I think he means an addon is creating popup messages for other addons, except it's impossible to tell that from static screenshots.

It may just be a feature of elvui, nothing in that addon list stands out to me.

It's a library actually, LibToast-1.0. It's included with Archy and newer releases of NPCScan along with some other addons I imagine. There's a config addon called Toaster available here that can be used to change some options of where and how the toasts appear, but if you just want to get rid of them both NPCScan and Archy have options to turn it off.