I'm trying to add items to the $social_icons_map and $social_icons arrays in class-twentynineteen-svg-icons.php

I know I need to do it in the functions.php file of my child theme. I think I need to make it happen after_setup_theme

However, I'm not sure if I need to rewrite the entire get_social_link_svg function, or if there's a way to extend the class just by adding those array values.

I've tried numerous variations of this solution which didn't work for me - just a lot of "The site is experiencing technical difficulty" pages. Lots of moving parts in this element (too many if you ask me) so I'm honestly not sure where to start. Please lend your thoughts.