MediaWiki:Common.js

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/* Any JavaScript here will be loaded for all users on every page load. */

// Define a function to be executed for non-logged-in users
function executeForNonLoggedInUsers() {
    // Disable Multimedia Viewer
    mw.config.set("wgMediaViewerOnClick", false);
}

// Hook into the appropriate event to execute the function
$(document).ready(function() {
    if (mw.config.get('wgUserId') === null) {
        executeForNonLoggedInUsers();
    }
});