WowAce

Upon (re)loading the UI, the following Lua error appears:

Message: Interface/AddOns/GatherMate2/Config.lua:1237: bad argument #1 to 'GetAddOnMetadata' (Invalid AddOn name WoWGatheringNodes. - Usage: local value = C_AddOns.GetAddOnMetadata(name, variable))
Time: Fri May 5 20:09:32 2023
Count: 1
Stack: Interface/AddOns/GatherMate2/Config.lua:1237: bad argument #1 to 'GetAddOnMetadata' (Invalid AddOn name WoWGatheringNodes. - Usage: local value = C_AddOns.GetAddOnMetadata(name, variable))
[string "=(tail call)"]: ?
[string "=(tail call)"]: ?
[string "=[C]"]: in function `GetAddOnMetadata'
[string "@Interface/AddOns/GatherMate2/Config.lua"]:1237: in function `CheckAutoImport'
[string "@Interface/AddOns/GatherMate2/Config.lua"]:1224: in function <Interface/AddOns/GatherMate2/Config.lua:1223>
[string "=[C]"]: ?
[string "@Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua"]:66: in function <Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua:61>
[string "@Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua"]:523: in function `EnableAddon'
[string "@Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua"]:536: in function `EnableAddon'
[string "@Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua"]:626: in function <Interface/AddOns/Ace3/AceAddon-3.0/AceAddon-3.0.lua:611>
[string "=[C]"]: in function `LoadAddOn'
[string "@Interface/FrameXML/UIParent.lua"]:545: in function `UIParentLoadAddOn'
[string "@Interface/FrameXML/UIParent.lua"]:754: in function `MajorFactions_LoadUI'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_DragonflightLandingPage.lua"]:100: in function `SetUpMajorFactionList'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_DragonflightLandingPage.lua"]:93: in function `RefreshMajorFactionList'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_DragonflightLandingPage.lua"]:88: in function `RefreshOverlay'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_DragonflightLandingPage.lua"]:80: in function <...sionLandingPage/Blizzard_DragonflightLandingPage.lua:76>
[string "=[C]"]: ?
[string "=[C]"]: in function `CreateFrame'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_DragonflightLandingPage.lua"]:49: in function `CreateOverlay'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_ExpansionLandingPage.lua"]:63: in function `RefreshExpansionOverlay'
[string "@Interface/AddOns/Blizzard_ExpansionLandingPage/Blizzard_ExpansionLandingPage.lua"]:35: in function <...pansionLandingPage/Blizzard_ExpansionLandingPage.lua:33>

Locals: (*temporary) = <function> defined =[C]:-1

Apparently according to the addon's code I'm EXPECTED to have the WoWGatheringNodes addon installed?

It's just a workaround but does remove the error.

Replace the line 1237 in config.lua looking like this...
local verline = GetAddOnMetadata(k, "X-Generated-Version")

...and put in this instead...

if k == "WoWGatheringNodes" then local verline = FALSE else  local verline = GetAddOnMetadata(k, "X-Generated-Version") end

This will stop GatherMate2 trying to import data from the WoWGatheringNodes addon. As the latter seems to be outdated anyways it should not be a problem to skip it.

Does not work for me :(

i replaced according line with you syntax and get the same error as before.

Change it into this:

local verline
if k == "WoWGatheringNodes" then
    verline = false
else
    verline = GetAddOnMetadata(k, "X-Generated-Version")
end