What exactly is "Browser" in Chrome's task manager, if it's not an open tab, and where is the traffic coming from?

I'm having problems loading some webpages on a slow coection on Chrome, and opened its Task Manager and saw that the "Browser" task is using up all the bandwidth to download something, but I don't know what it is downloading or how to stop it.

This is very inconvenient in slow speed coections such as 128 kilobits/second. Whenever there is download traffic in "Browser", it stalls the page loads of several tabs as this task is using up all the available bandwidth.

What is the source of "Browser" and its download activity? Extensions have their own tasks on the list but no download activity is coming from there. I also have no file downloads ruing in the background.