How to make some special character string as bold in javascript while using text plugin

i want to make this text "|| something 1 || something 2 || more || last one ||"

and then bold "|" all that string

then its became something this "|| something 1 || something 2 || more || last one ||"

I'm using typewriter text plugin from gsap this is my code

function boldString(str, substr) {
            var strRegExp = new RegExp(substr, 'g');
            return str.replace(strRegExp, '<b>' + substr + '</b>');
        }

gsap.to('.lead', { duration: '3.5', delay: '2', text: boldString("|| something 1 || something 2 || more || last one ||", "|")

then give me this result after typewriter plugin successfully launch

"||||| |s|o|m|e|t|h|i|n|g| |1| ||||| |s|o|m|e|t|h|i|n|g| |2| ||||| |m|o|r|e| ||||| |l|a|s|t| |o|n|e| |||||"

but with some "|" are bold

I'm also modified my code into

return str.replace(substr, '<b>' + substr + '</b>');

then gave me this result

|| something 1 || something 2 || more || last one ||

this is my reference before: Bold part of String

Thank you