firewalls are like condoms
they can stop it
but they can be broken by anything you don't want
Wat do then, I don't download sketchy things, only certified stuff, like from steam and websites. I always look up whether or not something is a virus. What about my brothers phone, his phone stopped changing backgrounds right as mine started.
Also, it is only image files, i think malware or somethign would affect other files too.