How to give canvas an id : <p>How can i give these canvas' in JS/html an id?</p>

<p>I want to make multiple flashing images on a single page and when I do only one image displays as there is no way to know which canvas to display, below is a link to my project.</p>

<p><a href="https://glitch.com/edit/#!/join/4cb25634-5dc4-45b8-8e28-060e6b1a98aa" rel="nofollow noreferrer">My project on glitch</a></p>
