Why don't browsers on Chromium load blocked sites with a VPN?

Question

Google Chrome

I use OpenVPN with my own VPS. There was a very specific problem, which I can not give any explanation. I don't even know how it's all intertwined. So, three sites are used for verification:
https://www.instagram.com/
https://twitter.com/
https://rutracker.org/

Each of them is not loaded in browsers on Chromium (Google Chrome, Opera, Edge , Vivaldi) with ERR_CONNECTION_RESET error.
There are three "buts":
1. All three open in Firefox.
2. Open in browsers on Chromium, if you distribute Wi-Fi from your smartphone.
3. They open in Chromium browsers if you use a simple and well-known plugin instead of your VPN - FastProxy .

Some browsers are brand new; so on cookies, plugins, etc. do not have to think. A similar story on the second laptop in the house. Colleagues use the same connection method but have no problems. And specifically, I had problems after the main Wi-Fi access point changed. Previously, no problems with loading pages were observed.

Does anyone have any idea where the problem might be? All my hypotheses refute each other.
- Is the provider to blame? In Firefox and Tor right now everything is ok.
- Blame the VPN or the server? In Firefox and Tor everything is ok.
Is Chromium to blame? When distributing the Internet from a smartphone, everything is ok.

There are absolutely no options for what to cling to. How can it work like that?

Answer 1

Raise any dns resolver on the VPS and push it as dns when raising OpenVPN

Answer 2

Install dns servers on the PC not automatically, but for example from cloudflare
1.1.1.1 1.0.0.1
Chrome takes dns from the Firefox system
uses public dns

Answer 3

There are absolutely no options for what to cling to.

check on the OpenVPN server in the file /etc/openvpn/server/server.conf
push "dhcp-option DNS 8.8.8.8"
push "dhcp-option DNS 8.8.4.4"
if there is a ; sign in front of them, if yes, then you need to uncomment ( remove the semicolon) well, register DNS if there are any other values, then restart the server

sudo systemctl restart [email protected]