Question about battery icon in Norton Tasks window

I'm an old time desktop computer user that uses external power only. I don't use a laptop or any other computing device that runs on battery power. That being said, I'm curious about the occasional appearance of a battery icon that appears next to the plug icon in the Power Source column in the Norton Tasks window.

 

Now and then a battery icon will appear next to the plug icon, (external power only), in the Identity Safe Maintenance line. This is one of the five lines that are grayed out at the bottom of Norton Tasks. I know they are for licensing and maintenance info.

 

Just curious why a battery icon appears now and then.

 

Thanks in advance.

 

 

Ed