User:Pandakekok9/bringBackOTRS.js

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function getImagesByAlt(alt) {
    let allImages = document.getElementsByTagName("img");
    let images = [];
    for (var i = 0, len = allImages.length; i < len; ++i) {
        if (allImages[i].alt == alt) {
            images.push(allImages[i]);
        }
    }
    return images;
}

var img = getImagesByAlt("OTRS Wikimedia")[0];
if (img) img.src = "https://upload.wikimedia.org/wikipedia/commons/thumb/1/1d/OTRS_Wikimedia.svg/70px-OTRS_Wikimedia.svg.png";