Off the top of my head, only combinators do not have specificity. So >, +, etc.
It’s not an HTML element, class, ID, pseudo class, or pseudo element. So thus it HAS no specificity .
You could have
table tr > td{}
table tr td{}
And the only thing that would ever allow the first rule to work is if you put it latter (ok ignore !important.)
So that means that the table tr>td{} is 0003 specificity while the table td:first-child{} is 0012 specificity. Order will not matter there.