There does not seem to be an easy overwrite without replicating the whole user interface. So the quickest solution might be to un-check the checkbox via JavaScript:
add_action('admin_footer', 'uncheck_send_user_notification');
function uncheck_send_user_notification() {
$currentScreen = get_current_screen();
if ('user' === $currentScreen->id) {
echo '<script type="text/javascript">document.getElementById("send_user_notification").checked = false;</script>';
}
}
The script is only injected on the user-new.php
page (see $currentScreen->id
), then selects the checkbox (see document.getElementById
) and sets checked to false
.
Update: Instead of checking for the current screen in the function there is the admin_footer-{$hook_suffix}
action that only runs on specific admin pages:
add_action('admin_footer-user-new.php', 'uncheck_send_user_notification');
function uncheck_send_user_notification() {
echo '<script type="text/javascript">document.getElementById("send_user_notification").checked = false;</script>';
}