data-duration attribute does not work

[olaulau]

data-duration attribute doesn't work, whereas value attribute works

tested on firefox & chromium, same behavior

https://codepen.io/olaulau/pen/XWLjxZr

even the src/index.html does not work as expected .

[trymeouteh]

Perhaps there is no need for the data-duration attribute since the value attribute works?

[dKally]

Yes, I've also observed this behavior with the data-duration attribute. I've submitted a pull request with a fix.