background-image not replaced webp format

Hello,

I add to wordpress logic Customize > Custom css code:

.bgimg-1-miedzynarodowa {
    background-image: url("https://www.ladtransport.com/wp-content/uploads/2019/11/tloparallaxwebp_1.jpg");
    min-height: 500px;
    position: relative;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
}

.caption-miedzynarodowa {
    position: absolute;
    left: 0;
    top: 45%;
    width: 100%;
    text-align: center;
    color: #000;
}

.caption-miedzynarodowa h1.border-miedzynarodowa {
    background-color: #f5ae3d;
    color: #fff;
    padding: 18px;
    font-size: 32px;
    letter-spacing: 2px;
    text-transform: uppercase;
    display: inline;
    font-weight: 700;
}

And the webp image not served but in this site: https://www.mkconcrete.pl i add this same code background-image in wordpress custom css and the image replaced webp. Why in this first site image not replaced webp?

Report details are:

Report number: RCZUWKZB
Report date: 01/13/2020 11:21:57

Best regards

• This topic was modified 6 years, 4 months ago by pbpiotr.

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