32x WQAchievements/WQAchievements.lua:2240: attempt to index field 'tooltip' (a nil value)
[string "@WQAchievements/WQAchievements.lua"]:2240: in function <WQAchievements/WQAchievements.lua:2238>
[string "=[C]"]: in function Hide' [string "@FrameXML/UIParent.lua"]:3265: in function HideUIPanel'
[string "@SharedXML/SharedUIPanelTemplates.lua"]:154: in function <SharedXML/SharedUIPanelTemplates.lua:145>

Locals:
(*temporary) = nil
(*temporary) =

{
activeTooltips = {
}
LabelPrototype = {
}
tooltipHeap = {
}
cellPrototype = {
}
tableHeap = {
}
providerMetatable = {
}
timerHeap = {
}
providerPrototype = {
}
onReleaseHandlers = {
}
LabelProvider = {
}
tipMetatable = {
}
frameHeap = {
}
IterateTooltips = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:162
CreateCellProvider = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:280
layoutCleaner = Frame {
}
tipPrototype = {
}
IsAcquired = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:154
Release = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:143
Acquire = defined @TipTac/ttCore.lua:415
cellMetatable = {
}
frameMetatable = {
}
}
(*temporary) = nil
(*temporary) = "attempt to index field 'tooltip' (a nil value)"
LibQTip = {
activeTooltips = {
}
LabelPrototype = {
}
tooltipHeap = {
}
cellPrototype = {
}
tableHeap = {
}
providerMetatable = {
}
timerHeap = {
}
providerPrototype = {
}
onReleaseHandlers = {
}
LabelProvider = {
}
tipMetatable = {
}
frameHeap = {
}
IterateTooltips = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:162
CreateCellProvider = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:280
layoutCleaner = Frame {
}
tipPrototype = {
}
IsAcquired = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:154
Release = defined @Rarity/Libs/LibQTip-1.0/LibQTip-1.0.lua:143
Acquire = defined @TipTac/ttCore.lua:415
cellMetatable = {
}
frameMetatable = {
}
}
WQA = {
watched = {
}
IsQuestFlaggedCompleted = defined @WQAchievements/WQAchievements.lua:2785
UpdateCustomRewards = defined @WQAchievements/Options.lua:1470
SetRewardLinkByID = defined @WQAchievements/WQAchievements.lua:2347
EnableModule = defined @Ace3/AceAddon-3.0/AceAddon-3.0.lua:328
modules = {
}
GetRewardForID = defined @WQAchievements/WQAchievements.lua:973
IterateEmbeds = defined @Ace3/AceAddon-3.0/AceAddon-3.0.lua:438
ToggleGet = defined @WQAchievements/Options.lua:1255
CreateCustomQuest = defined @WQAchievements/Options.lua:1341
PopUp = WQAchievementsPopUp {
}
debug = false
isQuestPinActive = defined @WQAchievements/WQAchievements.lua:2774
slash = defined @WQAchievements/WQAchievements.lua:507
SetDefaultModulePrototype = defined @Ace3/AceAddon-3.0/AceAddon-3.0.lua:405
newTasks = {
}
Show = defined @WQAchievements/WQAchievements.lua:798
itemList = {
}
defaultModuleState = true
AnnouncePopUp = defined @WQAchievements/WQAchievements.lua:2202
IsEnabled = defined @Ace3/AceAddon-3.0/AceAddon-3.0.lua:447
ExpansionList = {
}
ScheduleTimer = defined @Ace3/AceTimer-3.0/AceTimer-3.0.lua:94
DisableModule = defined @Ace3/AceAddon-3.0/AceAddon-3.0.lua:346
activeTasks = {
}
emissaryRewards = true
missionList = {
}
CreateCustomMissionReward = defined @WQAchievements/Options.lua:1600
UpdateOptions = defined @WQAchievements/Options.lua:161
GetArgs = defined @Ace3/AceConsole-3.0/AceConsole-3.0.lua:140
data = {

That definitely helps. Very good description.

Preventing the error should be pretty easy. I just have to check whether the tooltip is active when we close the main window.

With the empty window, I don't know how complicated it is. Maybe I'll leave that for later.

Can you reproduce the error or does it happen more or less randomly every now and then?

Does this also happen if you deactivate your other addons?

Seems to happen under the following circumstances:

I log into game.

I have WQA set to load after 20 seconds (don't think that makes any difference), so my screen something like this:

If I don't close WQA and leave it until I go AFK or manually go afk with /AFK, I have an addon called "AFK Fullscreen Warning" that kicks in and shows a nice AFK screen e.g.

When I come back to my PC and come out of being AFK, the WQA screen is still there, but is now blank e.g.

When I close the WQA window, that is when the LUA happens e.g.

Doesn't seem that I can reproduce it when I disable "AFK Fullscreen Warning" addon.

I hope this helps?