What is petty foibles?

Answer 1

petty foibles has two words, so divide them and you get petty, foibles,

Petty is given these definitions;1: having secondary rank or importance : minor, subordinate

2: having little or no importance or significance

3: marked by or reflective of narrow interests and sympathies : simpleminded

So guessing that 2 is the one we need, we now get no significant foibles.

Foibles can be defined as in these two instances;

1: the part of a sword or foil blade between the middle and point

2: a minor flaw or shortcoming in character or behavior : weakness foibles>

so, now we can equate that it is probably translated into;

"No significant shortcoming"