This is a source code in pure JS to convert widely unsupported WebP format to JPG format (PNG also possible)
After execuing a website with this code and setting URL-TO-WEBP-IMAGE the webpToJpg converts image from WebP to JPG and places it inside the img. It works only in browser supporting WebP, so mainly Chrome.
<img id='a' src='URL-TO-WEBP-IMAGE' />
<script>
function webpToJpg(id) {
var image = new Image();
image.onload = function () {
var canvas = document.createElement('canvas');
canvas.width = this.naturalWidth;
canvas.height = this.naturalHeight;
canvas.getContext('2d').drawImage(this, 0, 0);
document.getElementById(id).src = canvas.toDataURL('image/jpeg');
};
image.src = document.getElementById(id).src;
}
webpToJpg('a');
</script>