PHP notice issues within wordpress admin page

I’m getting the following notice when I enable the plugin and navigate to my site’s admin page.
Notice: trying to get property of non-object in /var/www/wp-content/plugins/mobile-css/mc-includes/mc.functions.php on line 159

This is fixable by editing mc.functions.php

function MC_styles() {

// get post
global $post;
+
+ if(!$post)
+ return;
+
// if we’re viewing mc_rule post type
if ( ‘mc_rule’ == $post->post_type ) {

https://wordpress.org/plugins/mobile-css/