Firefox keeps loading Twitch data when all Twitch tabs are closed

Question

I just noticed that something was using up about 500KB/s of (down) internet connection in the background. After checking more in details, I found out that this was used by Firefox, with a connection to 185.42.204.42:443, which then switched to 52.223.195.225:443. Both are Twitch IPs.

I don't have a single Twitch tab opened. I don't have a single stream running in any of my Firefox tabs. And yet, somehow, Firefox is loading 500KB/s of Twitch data in the background.

Is there a way to disable all background activity in Firefox? Something like: when I close a tab, terminate it fully and immediately, like I've always expected it to behave in the first place? I tried searching but all I found was someone with an AVG issue there https://support.mozilla.org/en-US/questions/997796

Using Fx 64 on Windows 10 x64

Answer 1

I finally found the cause of this "problem": one of the sites I had in my always opened tabs was actually playing a Twitch stream silently in the background :x