[Branda] Issue with JS script on Admin Footer

We were using Branda to add a snippet of code to the footer of the admin area on our site, using the “Admin Footer” module. When we used the .replaceWith on the body tag of the admin page it worked. So, we replaced the backend body of every admin page with “TEST”, using the following code:

<script>
jQuery(document).ready(function() {
jQuery('body').replaceWith('TEST');
});
</script>

But, after that, we were not able to access the admin pages anymore. We couldn’t access the Branda admin page to remove the code. We restored our site from a backup but the issue was still there.

We disabled the plugin from FTP by renaming the folder name, but we use the plugin for things and need it. Please advise.