I'm not aware there is such a list. Logically it's mostly small countries where they speak their own languages where no big corporations that produce ads have any interest in. You probably will find some comment like mine where they mention certain countries but this can always change any day. Sometime there is a single advetiser in a country but even then you will see their ad much less frequently than the common US/English based ads.

I can recommend you the Nord Vpn Firefox addon which allows you to only use vpn for certain domains which would be anything with *.twitch.tv

Same as on other platforms twitch ads are location based or in this case ip geo location. They are notoriously fighting ad blockers and have long been opting into ad stream injection which is why most common ad blocking techniques won't work. Basically after all the custom script solutions, like vaft script, started failing l started testing around with VPN taking advantage of the location based aspect of ads. Basically there are countries where noone is paying for running ads. E.g. Czech republic. So basically the most secure way to block ads on twitch is Vpn to certain countries. However I noticed that you need to use IPs from that country for about a day. It seems they are caching your Ip for some but after that you wont get any ads. You can read about all known ad solutioms of twitch here: https://github.com/pixeltris/TwitchAdSolutions

Also this does not work with the twitch mobile app and neither with the mobile version of twitch in a mobile browser. However it does work when switching to the desktop version in your mobile browser. So desktop version while using vpn on your phone should work. At least when I tested it last.

See my update in the post, now everything makes a little more sense and it is for sure related to the split tunneling feature.

No I am not sure, I don't really see any error message, just a timeout. Not sure how an error of the DNS resolver looks like compared to any error caused by a timeout. However the DNS resolution should indeed be returning a different error, at least when entering a random non existing URL Firefox returns "server not found" instead of "problem loading page"(and NS_ERROR_NET_TIMEOUT in network debugging consoel). But what else could it be? It is so strange that the combination of Firefox and NordVPN extension does work, so it seems that the routing through the vpn network generally works, so it actually has to be something with the windows client interaction I guess.

I think you should all chill out a bit in the comments. It is totally fine to hint at problems for disabled persons. Of course Op could have used different wording but I think their noble intent is clear. Now of course it would be nice that Op already presented a set of solutions to the problem they noticed but it is totally fair to not have them. I'm sure there are decent alternatives to visual-only captchas. So instead of telling Op to "fuck off" you could all be either ignore this request or try to actually be a decent human being and offer possible solutions. Now of course the admins have to decide it those other options are technically feasible. You have to keep in mind that many small instances do not have resources to those kind of technical experiments when they don't work out of the box.

Weawow is a completly (also ad-)free weather forecast app run basically solo by a Japanese guy. I was surprised when I found this app that it was so good in every aspect that I had to donate the guy. It has has more than half a Mio. reviews on google play with an average of 4.9 . Idk of any free app with that many reviews having this kind of rating, well deserved.

Further honorable mentions:

• Vivaldi browser
• Joplin notes app
• nextcloud
• wikipedia (obviously)
• Öffi
• Signal
• keepass
• rif for reddit (R.I.P)