trim() does not work on extra space between characters in javascript code example

Example 1: js method string remove extra spaces

const sentence = '    My string with a    lot   of Whitespace.  '.replace(/\s+/g, ' ').trim()

// 'My string with a lot of Whitespace.'

Example 2: javascript trim

var str=" I have outer spaces ";
var cleanStr=str.trim();//trim() returns string with outer spaces removed