Removing all video inside of the youtubes watch later playlist.

clearWatchLater.js

var clearTimer;
function clearWatchList(interval) {clearTimer = setInterval(clearWatchLater, interval);}
function getButtonAttr() {
    var elemArray = document.querySelectorAll("#button");
    return elemArray[37].getAttribute("aria-label");
}

function getPlaylistName() {
    var playlistElem = document.getElementById("text-displayed");
    return playlistElem.innerHTML;
}

function clearWatchLater(buttonName, fieldName) {
    var selectorLabel = getButtonAttr();
    var playlistName = getPlaylistName();

    document.querySelector(`#primary button[aria-label="${selectorLabel}"]`).click();
var things = document.evaluate(`//span[contains(text(),"${playlistName}")]`,document,null,XPathResult.ORDERED_NODE_SNAPSHOT_TYPE,null);
    if (things.snapshotLength = 0) {killSwitch()}
    for (var i = 0; i < things.snapshotLength; i++) {
        things.snapshotItem(i).click();
    }
}
function killSwitch() {
  clearInterval(clearTimer);
}