blockwishlist module change Icon

[Jimbob]

Hi

I am trying to change the icons displayed by the blockwishlist module.

Those hearts icons:

 

I can see in the chrome inspector that those are material icons:

<i class="material-icons">favorite_border</i>

basically i would like to change them for png that i choose.

but i can't find which .tpl should i modifiy for doing this?

 

Thank you for your help