Undefined index: HTTP_USER_AGENT

Hey,

I’m seeing a lot of these in my error logs:

php[error] [26-Mar-2015 17:12:54 UTC] PHP Notice: Undefined index: HTTP_USER_AGENT in /data/wp-content/plugins/bj-lazy-load/bj-lazy-load.php on line 50

Any idea why and how to fix it?

Thanks!

https://wordpress.org/plugins/bj-lazy-load/