Youtube Playlist Total Time Length Finder for Firefox Web Console

youtube-playlist-total-lengt-finder.js

var collection = document.getElementsByClassName("style-scope ytd-thumbnail-overlay-time-status-renderer");

var arr = []

for (var i = 0; i < collection.length; i++) {
    if (collection[i].tagName.endsWith('SPAN')) {
        arr.push(collection[i]);
    }
}

var total_sec = 0;

for (var j = 0; j < arr.length; j++) {
    var hms = arr[j].firstChild.textContent.trim().split(":");
    if (hms.length == 3) {
        total_sec += parseInt(hms[2].trim()) + (parseInt(hms[1].trim()) * 60) + (parseInt(hms[0].trim()) * 60 * 60);
    } else if (hms.length == 2) {
        total_sec += parseInt(hms[1].trim()) + (parseInt(hms[0].trim()) * 60);
    } else if (hms.length == 1) {
        total_sec += parseInt(hms[0].trim());
    }
}
var date = new Date(null);
date.setSeconds(total_sec);
var result = date.toISOString().substr(11, 8);
console.log("Total lenght of this playlist is: " + result);