Not sure if this is required any more but this is how we used to add a message to a site for browsers using old versions of IE.
Functions:
<?php require get_template_directory() . '/components/browse-happy/template-tags-browser.php';
Add this to the header.php
<body <?php body_class(); ?> > // add this line below... <?php gomo_browse_happy() ?>
Template tag code:
<?php
function gomo_browse_happy() {
?>
<!--[if lte IE 8]>
<div class="browsehappy-container"><p class="browsehappy">You are using an <strong>outdated</strong> browser.<br />Please <a href="https://browsehappy.com/">upgrade your browser</a> to view this site.</p></div>
<![endif]-->
<?php
gomo_browser_styles ();
}
function gomo_browser_styles () {
?>
<style>
.browsehappy-container {
position: fixed;
left: 0px;
top: 0px;
right: 0px;
bottom: 0px;
width: 100%;
height: 100%;
z-index: 99999;
background:black;
margin: 0px;
padding: 0px;
text-align: center;
font-size: 60px;
line-height: 90px;
color: white;
}
.browsehappy {
margin: 10% auto;
width:80%;
max-width: 800px;
text-align: center;
font-size: 30px;
line-height: 40px;
color: white;
}
.browsehappy a {
color: white;
}
</style>
<?php
}
add_action( 'wp_head', 'gomo_browser_styles', 1 );
?>