Ran into this bug twice in a row on the Alliance Grizzly Hills guide:

1x WoWPro_Leveling-1.6.1\WoWPro_Leveling_Parser.lua:882: attempt to concatenate field '?' (a nil value)
WoWPro_Leveling-1.6.1\WoWPro_Leveling_Parser.lua:667: in function `EventHandler'
WoWPro-1.6.1\WoWPro_Broker.lua:159: in function <WoWPro\WoWPro_Broker.lua:136>

Locals:
self =

{
SetDefaultModuleLibraries = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:381:
AutoCompleteZone = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:837:
OnInitialize = @ WoWPro_Leveling\WoWPro_Leveling.lua:11:
NewModule = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:255:
EnableModule = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:346:
modules = {}
GetModule = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:230:
IterateEmbeds = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:456:
actionlabels = {}
defaultModuleLibraries = {}
UpdateQuestTracker = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:868:
AutoCompleteLoot = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:805:
Tags = {}
GetName = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:298:
RowUpdate = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:380:
name = "WoWPro_WoWPro Leveling"
IsEnabled = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:465:
SkipStep = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:170:
DisableModule = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:364:
FirstMapCall = false
NextStep = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:42:
baseName = "WoWPro_Leveling"
UpdateGuideList = @ WoWPro_Leveling\WoWPro_Leveling_GuideList.lua:24:
actiontypes = {}
CompletingQuest = false
LoadGuide = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:310:
GuideList = {}
AutoCompleteLevel = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:853:
AutoCompleteSetHearth = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:822:
AutoCompleteQuestUpdate = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:741:
IsModule = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:237:
PopulateQuestLog = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:691:
SetDefaultModuleState = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:401:
CreateCurrentGuideTitle = true
AutoCompleteGetFP = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:679:
OnDisable = @ WoWPro_Leveling\WoWPro_Leveling.lua:61:
NextStepNotSticky = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:154:
enabledState = true
RegisterEvents = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:622:
Disable = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:328:
UnSkipStep = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:211:
EventHandler = @ WoWPro_Leveling\WoWPro_Leveling_Parser.lua:639:
Enable = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:313:
CreateConfig = @ WoWPro_Leveling\WoWPro_Leveling_Config.lua:196:
IterateModules = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:451:
SetEnabledState = @ AtlasLoot\Libs\AceAddon-3.0\AceAddon-3.0.lua:438:
RegisterGuide = @ WoWPro_Leveling\WoWPro_Leveling.lua:81:
OnEnable = @ WoWPro_Leveling\WoWPro_Leveling.lua:16:
moduleName = "WoWPro Leveling"
SetDefaultModulePrototype = defined @AtlasLoot\Libs\Ac

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