Not working at all.

1x ...dOns\SavedInstances\Libs\LibQTip-1.0\LibQTip-1.0-47.lua:540: attempt to call method 'SetBackdrop' (a nil value)
[string "@SavedInstances\Libs\LibQTip-1.0\LibQTip-1.0-47.lua"]:540: in function <...dOns\SavedInstances\Libs\LibQTip-1.0\LibQTip-1.0.lua:534>
[string "@SavedInstances\Libs\LibQTip-1.0\LibQTip-1.0-47.lua"]:127: in function Acquire' [string "@SavedInstances\Core\Core.lua"]:3282: in function ShowTooltip'
[string "@SavedInstances\Core\Core.lua"]:2401: in function <SavedInstances\Core\Core.lua:2399>
[string "@titan\LDBToTitan.lua"]:327: in function <Titan\LDBToTitan.lua:286>

Locals:
tooltip = {
0 =
scrollChild = {
}
scrollFrame = {
}
}
key = "SavedInstancesTooltip"
backdrop =

{
backdropColor = {
}
edgeSize = 16
tileEdge = true
backdropBorderColor = {
}
tileSize = 16
edgeFile = "Interface/Tooltips/UI-Tooltip-Border"
tile = true
bgFile = "Interface/Tooltips/UI-Tooltip-Background"
insets = {
}
}
(*temporary) = nil
(*temporary) = {
0 =
scrollChild = {
}
scrollFrame = {
}
}
(*temporary) = {
backdropColor = {
}
edgeSize = 16
tileEdge = true
backdropBorderColor = {
}
tileSize = 16
edgeFile = "Interface/Tooltips/UI-Tooltip-Border"
tile = true
bgFile = "Interface/Tooltips/UI-Tooltip-Background"
insets = {
}
}
(*temporary) = "attempt to call method 'SetBackdrop' (a nil value)"
GameTooltip = GameTooltip {
0 =
OnBackdropLoaded = defined @SharedXML\Backdrop.lua:205
ItemTooltip = {
}
SetHyperlink = defined =[C]:-1
RightEdge = {
}
ClearBackdrop = defined @SharedXML\Backdrop.lua:335
SetLFGDungeonReward = defined @AllTheThings\AllTheThings.lua:4666
SetRecipeReagentItem = defined @Altoholic\Tooltip.lua:702
SetBuybackItem = defined =[C]:-1
SetMerchantItem = defined =[C]:-1
SetupTextureCoordinates = defined @SharedXML\Backdrop.lua:267
TopRightCorner = {
}
GetEdgeSize = defined @SharedXML\Backdrop.lua:241
updateTooltip = 0.050000
SetInventoryItem = defined =[C]:-1
TopEdge = {
}
SetLootRollItem = defined =[C]:-1
SetBagItem = defined =[C]:-1
BottomRightCorner = {
}
SetBackdropColor = defined @SharedXML\Backdrop.lua:452
LeftEdge = {
}
SetCurrencyByID = defined @AllTheThings\AllTheThings.lua:4628
textLeft1Font = "GameTooltipHeaderText"
SetCurrencyToken = defined @Altoholic\Tooltip.lua:702
SetGuildBankItem = defined =[C]:-1
TopLeftCorner = {
}
Hide = defined =[C]:-1
TextRight1 = GameTooltipTextRight1 {
}
ApplyBackdrop = defined @SharedXML\Backdrop.lua:347
SetBackdrop = defined @SharedXML\Backdrop.lua:382
comparing = false
TopOverlay = {
}
GetBackdropBorderColor = defined @SharedXML\Backdrop.lua:462
GetBackdrop = defined @SharedXML\Backdrop.lua:400
SetTrainerService = defined =[C]:-1
SetHeirloomByItemID = defined =[C]:-1
SetQuestItem = defined =[C]:-1
SetBorderBlendMode = defined @SharedXML\Backdrop.lua:319
SetToyByItemID = defined =[C]:-1
SetLootItem = defined =[C]:-1
BottomLeftCorner = {
}
SetInboxItem = defined =[C]:-1
HasBackdropInfo = defined @SharedXML\Backdrop.lua:331
TextLeft1 = GameTooltipTextLeft1 {
}
BottomEdge = {
}
SetLFGDungeonShortageReward = defined @AllTheThings\AllTheThings.lua:4683
Center = {
}
OnBackdropSizeChanged = defined @SharedXML\Backdrop.lua:235
SetTradeTargetItem = defined =[C]:-1
GetBackdropColor = defined @SharedXML\Backdrop.lua:443
SetTradePlayerItem = defined =[C]:-1
textRight1Font = "GameTooltipHeaderText"
SetSendMailItem = defined =[C]:-1
SetItemByID = defined =[C]:-1
SetBackdropBorderColor = defined @SharedXML\Backdrop.lua:475
textLeft2Font = "GameTooltipText"
textRight2Font = "GameTooltipText"
TextRight2 = GameTooltipTextRight2 {
}
TextLeft2 = GameTooltipTextLeft2 {
}
SetExistingSocketGem = defined =[C]:-1
shoppingTooltips = {
}
backdropInfo = {
}
SetItemKey = <function

Since you didn't answer the questions in bug report template and I can't reproduce this. :( I have some question for you to gather information.

• What is your SI version?
• What is your WoW version?
• Did you try to let SI be your only enabled addon?

What is your SI version? 9.0.0
What is your WoW version? 9.0.1.36230
Did you try to let SI be your only enabled addon? Yes

The error is being caused by Titan Panel. It happens with Titan Panel version 5.19.0.90001a and older version 5.18.7.80300.

Thanks for your reply. I guess I need to wait for a Titan Panel update so feel free to close this report.