Consolidated the fixes submitted by jrowles & fubaWoW - haven't had any errors since.

In file VendorerStackSplitFrame.lua

change line #656 from:

return tonumber(currencyID), info;

to:

return tonumber(currencyID), info.name, info.quantity, info.iconFileID, info.quantityEarnedThisWeek, info.maxWeeklyQuantity, info.maxQuantity, info.discovered, info.quality;

In file !Vendorer.toc

Change line #1 from:

## Interface: 90001

to:

## Interface: 90005

AND

change line #5 from:

## Version: 4.0.1

to:

## Version: 4.0.2

in file CHANGELOG.md

change the first 6 lines or so to reflect the following:

4.0.2

• Patch 9.0.5
• Remove gained/lost summary after closing the vendor UI. Blizzard added their own message for this.

4.0.1

• Attempted blind fix at a nil error.

in file core.lua

change lines #1769 through 1777 from:

local diff = tonumber(GetMoney() - Addon.PlayerMoney);
local moneystring = GetCoinTextureString(math.abs(diff));

if(diff > 0) then
	Addon:Announce("|cff73ce2fGained|r " .. moneystring);
elseif(diff < 0) then
	Addon:Announce("|cfff0543eLost|r " .. moneystring);
end

to

- local diff = tonumber(GetMoney() - Addon.PlayerMoney);
- local moneystring = GetCoinTextureString(math.abs(diff));
-
- if(diff > 0) then
-	Addon:Announce("|cff73ce2fGained|r " .. moneystring);
- elseif(diff < 0) then
-	Addon:Announce("|cfff0543eLost|r " .. moneystring);
- end
-

If for some reason you're having issues - you can PM me via curseforge.com @ wraithlord2015

If you are still using the addon, I've created a PR for #Dragonflight that should fix most if not all of the reported open issuess.

Feel free to use #32 or download from https://github.com/sebid/Vendorer/archive/refs/heads/master.zip