WowAce

1x [ADDON_ACTION_BLOCKED] AddOn 'Ace3' tried to call the protected function 'UNKNOWN()'.
[!BugGrabber/BugGrabber.lua]:554: in function '?'
[!BugGrabber/BugGrabber.lua]:538: in function <!BugGrabber/BugGrabber.lua:538>
[C]: ?
[C]: ?
[C]: in function 'SetScale'
[Mapster/Mapster.lua]:230: in function 'SetScale'
[Mapster/Mapster.lua]:242: in function <Mapster/Mapster.lua:241>
[tail call]: ?
[C]: in function 'SynchronizeDisplayState'
[Blizzard_WorldMap/QuestLogOwnerMixin.lua]:158: in function 'SetDisplayState'
[Blizzard_WorldMap/QuestLogOwnerMixin.lua]:84: in function 'HandleUserActionMinimizeSelf'
[Blizzard_WorldMap/Blizzard_WorldMap.lua]:106: in function 'minimizedCallback'
...[C]: in function 'Show'
[Blizzard_UIParentPanelManager/Shared/UIParentPanelManager.lua]:839: in function <...UIParentPanelManager/Shared/UIParentPanelManager.lua:825>
[C]: ?
[C]: ?
[C]: in function 'ShowUIPanel'
[Blizzard_WorldMap/QuestLogOwnerMixin.lua]:115: in function 'SetDisplayState'
[Blizzard_WorldMap/QuestLogOwnerMixin.lua]:51: in function 'HandleUserActionToggleSelf'
[Blizzard_WorldMap/Blizzard_WorldMap.lua]:581: in function <...rfaceBlizzard_WorldMap/Blizzard_WorldMap.lua:576>
[C]: in function 'ToggleWorldMap'
[TOGGLEWORLDMAP]:1: in function <[string "TOGGLEWORLDMAP"]:1>

Locals:
self=<table>
event="ADDON_ACTION_BLOCKED"
addonName="Ace3"
addonFunc="UNKNOWN()"
name="Ace3"
badAddons=<table>{
Ace3=true
}
L=<table>{
NO_DISPLAY_2="|cffffff00The standard display is called BugSack, and can probably be found on the same site where you found !BugGrabber.|r"
ERROR_DETECTED="%s |cffffff00captured, click the link for more information.|r"
BUGGRABBER_STOPPED="|cffffff00There are too many errors in your UI. As a result, your game experience may be degraded. Disable or update the failing addons if you don't want to see this message again.|r"
USAGE="|cffffff00Usage: /buggrabber <1-%d>.|r"
STOP_NAG="|cffffff00!BugGrabber will not nag about missing a display addon again until next patch.|r"
NO_DISPLAY_STOP="|cffffff00If you don't want to be reminded about this again, run /stopnag.|r"
NO_DISPLAY_1="|cffffff00You seem to be running !BugGrabber with no display addon to go along with it. Although a slash command is provided for accessing error reports, a display can help you manage these errors in a more convenient way.|r"
ERROR_UNABLE="|cffffff00!BugGrabber is unable to retrieve errors from other players by itself. Please install BugSack or a similar display addon that might give you this functionality.|r"
ADDON_CALL_PROTECTED="[%s] AddOn '%s' tried to call the protected function '%s'."
}

based on the error, this should be cross reported to mapster. they are using ACE3 and it is likely mapster tat has the issue, via its ACE3 call