No Stupid Questions

While blocking would me too much. It could be nice of there would exist a fact checking browser extension that would warn if lies as thrown I don't even know how that could work though.

I would only block 4chan, patriotfront, and other stuff that most people would never know about where the cesspool is known to be malicious and full of white nationalist instigators, if anything. But then again, it would never occur to me to try to trick a family member.

If your uncle isn't already lost, you might be able to gently talk about this stuff. There are people who discuss how to carefully offload alt-right beliefs by asking questions that reveal fallacy rather than beating someone over the head with why they're wrong. You can find better info than I have by searching the web.

My own mother, for example, voted for Trump three times. That relationship is over, sadly. Some people can't be reached.

Moral: don't do underhanded shit. Be open about your disagreement, but first learn what approaches have the greatest chance of success.

ubo will do the trick by blocking (political) ads that promote those bs. you can use custom filter list if you know what sites to block but at this point it somewhat feels like parental censorship. talking to him about politics and the misinformation campaigns is a much better idea to keep your uncle less susceptible to such brainwashing even outside online world. initially it might feel pointless but perseverance is the key.

If he's living with you, you could try to block it at the router/firewall level.

On the machine, I'd just make it really slow rather than block it outright. Make it as unpleasant as possible to access those sites without blocking them outright. Making them slow makes it look like the sites suck. Blocking them makes it look like you did it or some conspiracy thing.

But if he lives with you, blocking them from your network is perfectly ethical imo

I think you should talk to him instead of being sneaky about it.

There is, but watch you don't fuel the "liberals have hacked my PC to hide the truth from me" conspiracy theories.

As basic as blocker goes a long way in preventing trash from showing up accidentally, though.

I suppose you could add entries for those right-wing websites into the "hosts" file, redirecting them to Google or some other relatively innocuous place.

This is a sticky situation if you try to implement it. At best you temp hide it from the uncle, at worse you double down the ideology because of conspiracy theories and end up hurting your relationship with your uncle, plus Anything you can do locally he could find workarounds for if he wanted to, especially since his friends will know the sites still exist.

He would likely accuse you immediately though as the last person to touch the system is always the one at fault, and you are the one setting it up.

To answer the question though, you could edit the host file to block known propaganda networks(by directing them to invalid ip's which would make it look like its down) but, that setup is not very effective and unless you can block all of them, hes just going to find ways around it or alternatives, and this system likely wouldn't survive most current day browsers that are pushing secure DNS such as firefox since cloudflare is going to know how to access it still.

I still don't think it's a good idea though, too many things that could go wrong out of it, plus hard pushing an agenda has never been a good way at convincing someone their mentality isn't right, this will just re-enforce his mentality out of spite.

Subscribe him to some left leaning newsletters, facebook groups, YT channels... whatever media he uses. It's been shown that simply exposing people to news from outside their bubble is enough to change their views.

If you think some of the opinions he's getting on the internet are propaganda/untrue/manipulation, you should explain it to him. You don't have any moral right to sneakily hide/block anything from other person just because you have different views.

A bit of sleuthing and I found https://filterlists.com/ that work with an ad-blocker of your choice. ublock origin and a "racist" or "conspiracy" filterlist should do the trick.

Some people just reach a point in life where their brains are just incapable of learning empathy. I would just cut ties if you can. Lile what happens when they wanna watch fox news and then it doesn't work? They'll just bother you again saying "the computer is broken".