On version C215.
A pretty niche set of circumstances but if you cast certain debuffs on a character with a certain character name it crashes the wow client of both the caster and the target (Maybe everyone around him with details also?). Possibly because of shortened class names, I first saw this with a warrior named War and it was reproducible every time. If he was mind controlled and I cast debuffs on him after a few debuffs from a warlock we both crash, a second account beside us without details was uneffected. Not sure if it was the amount of debuffs that triggered it or certain debuff names but it happened after a few casts every time, was a bit hard to test further the warrior was busy world buffing at the time. Feel free to msg me @Venomisto on either of the UI dev discords if you need more details.

Message: Interface\AddOns\Details\classes\container_pets.lua:50: stack overflow
Time: Sun Jan 10 12:40:12 2021
Count: 1
Stack: Interface\AddOns\Details\classes\container_pets.lua:50: stack overflow
...Ons\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:758: in function <...Ons\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:717>
[C]: in function find' Interface\AddOns\Details\classes\container_pets.lua:50: in function PegaDono'
...ace\AddOns\Details\classes\container_combatentes.lua:499: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ... ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente' ...ace\AddOns\Details\classes\container_combatentes.lua:502: in function PegarCombatente'
...ace\AddOns\Details\classes\container_combatentes.lua:395: in function <...ace\AddOns\Details\classes\container_combatentes.lua:386>
(tail call): ?
...ace\AddOns\Details\classes\container_combatentes.lua:513: in function `PegarCombatente'
Interface\AddOns\Details\core\parser.lua:567: in function <Interface\AddOns\Details\core\parser.lua:421>
(tail call): ?

Locals: errMsg = "Interface\AddOns\Details\classes\container_pets.lua:50: stack overflow"
isBugGrabber = nil
tsmErrMsg = nil
oldModule = nil
private =

{
globalNameTranslation = {
}
FormatErrorMessageSection = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:517
ErrorHandler = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:134
origErrorHandler = defined @interface\AddOns\RCLootCouncil_Classic\RCLootCouncil\Core\ErrorHandler.lua:144
hitInternalError = false
CreateErrorFrame = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:536
num = 0
SanitizeString = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:510
AddonBlockedHandler = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:502
GetStackLevelInfo = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:344
ParseLocals = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:396
ignoreErrors = false
errorReports = {
}
IsTSMAddon = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:478
localLinesTemp = {
}
GetStackInfo = defined @interface\AddOns\TradeSkillMaster\LibTSM\Service\ErrorHandler.lua:313
}
MAX_STACK_DEPTH = 50
OLD_TSM_MODULES = {
1 = "TradeSkillMaster_Accounting"
2 = "TradeSkillMaster_AuctionDB"
3 = "TradeSkillMaster_Auctioning"
4 = "TradeSkillMaster_Crafting"
5 = "TradeSkillMaster_Destroying"
6 = "TradeSkillMaster_Mailing"
7 = "TradeSkillMaster_Shopping"
8 = "TradeSkillMaster_Vendoring"
9 = "TradeSkillMaster_Warehousing"
}

Random data point: my pally Pal doesn't trigger this

edit: didn't try to get it mind controlled