transparency item font

hey guys,

for my first account items look like this: for my second account it looks like this: as you see, for the first the background of the font is Black, for the second it is transparent
do you know if this is a setting?
i prefer the Black background but wasn't able to find out how to set it.

is it possible that some of the accounts are using some mod, and you don't remember?
Or the second account is using classic graphic (non-Resurrected)?
(There is a

Key to toggle this on/off)