The hover hint suggests "Ennek ellenére sem" so but I got "Ennek ellenére sem, köszönöm" wrong. Reported (but I don't know if the hover hint is wrong or my answer is wrong).
I guess "ennek ellenére sem" would be used for something like "In spite of this, I still don't ...". Or "not even if ... " something.
In a positive sentence, it is just "ennek ellenére".
If the whole sentence was in negation, then it would be "Ennek ellenére sem". Otherwise it isn't.
When would you use this sentence? It seems like a tongue in cheek thankyou.
"We failed, the kingdom is lost. But still, thank you for your help."
A fitting statement for your avatar!
I'll take it as a compliment. :D