Error in directive tooltip bind hook: "TypeError: classList.indexOf is not a function"

[mickeyklai]

TypeError: classList.indexOf is not a function
at eval (v-tooltip.esm.js?455e:2456)
at Array.forEach ()
at addClasses (v-tooltip.esm.js?455e:2455)
at createTooltip (v-tooltip.esm.js?455e:3382)
at bind (v-tooltip.esm.js?455e:3414)
at callHook$1 (vue.esm.js?65d7:5855)
at _update (vue.esm.js?65d7:5780)
at Array.updateDirectives (vue.esm.js?65d7:5761)
at invokeCreateHooks (vue.esm.js?65d7:5299)
at createElm (vue.esm.js?65d7:5190)

v-tooltip version: v-tooltip@2.0.0-rc.20

The element in which it fails in the function addClasses is svg. ie: (el = svg, classList = SVGAnimatedString)

function addClasses(el, classes) {
var newClasses = convertToArray(classes);
var classList = convertToArray(el.className);
newClasses.forEach(function (newClass) {
if (classList.indexOf(newClass) === -1) {
classList.push(newClass);
}
});
el.className = classList.join(' ');
}

I made the following changes here and in the removeClasses function for it to work properly:

function addClasses(el, classes) {
var newClasses = convertToArray(classes);
var classList = convertToArray(el.className);
if (classList instanceof SVGAnimatedString)
classList = Array.from(classList);
newClasses.forEach(function (newClass) {
if (classList.indexOf(newClass) === -1) {
classList.push(newClass);
}
});
if (el instanceof SVGElement)
el.setAttribute('class', classList.join(' '));
else
el.className = classList.join(' ');
}

Thanks