i think there is conflict with Blizzard challenges UI
screen shot with addone on

Screen shot with addone off

100x dOns\Blizzard_ChallengesUI\Blizzard_ChallengesUI.lua:225: attempt to index field '?' (a nil value)
[string @Blizzard_ChallengesUI\Blizzard_ChallengesUI.lua"]:225: in function `ChallengesFrame_Update'
[string @Blizzard_ChallengesUI\Blizzard_ChallengesUI.lua"]:134: in function <...dOns\Blizzard_ChallengesUI\Blizzard_ChallengesUI.lua:125>

https://github.com/Gethe/wow-ui-source/blob/1cf759abedf90eaf4adaa1be3629855626c2d998/AddOns/Blizzard_ChallengesUI/Blizzard_ChallengesUI.lua#L134

any news about this error @Ironii ?

do you get that error often or always at the specific situation? I got that error once and it seemed more like a default ui bug than anything else (something to do with getting wrong (character) data from the server, seems like it happens quite a bit atm)

i got it everytime i log a character

Ty 💯

turns out that force loading Blizzard_ChallengesUI before loading screen was over, would cause it to error out, when its fresh login (per exe launch) on a character that has completed at least one mythic+ this week.
Fixed on the newest version