ERR_QUIC_PROTOCOL_ERROR on first time load page. How can I fix?

I am encountering an issue where the initial page load fails for my client users specifically on Chrome/PC. The condition is as follows: My website utilizes a proxy via Cloudflare DNS and has the QUIC protocol enabled. When I disable the QUIC protocol, I receive an ERR_HTTP2_PROTOCOL_ERROR. This error occurs consistently on every page during the initial loading phase. However, when I remove the proxy via Cloudflare DNS, the error disappears. I am seeking assistance in understanding what might be causing this issue with my site configuration and how to resolve it while still utilizing the Cloudflare proxy.

So I want someone explains what happen to my site, did I set something wrong?
How to fix this error when I still use proxy vis Cloudflare?

This is my website URL :

[type or paste code here](


I’m not too sure about the ERR_QUIC_PROTOCOL_ERROR - but I know that the ERR_HTTP2_PROTOCOL_ERROR occurs when there is a malformed HTTP response header - Chrome is strict in how it enforces the syntax of HTTP response headers, and if there is a formatting/syntax error then it generates this error. I"m assuming that this is the same cause for the QUIC error just with HTTP/3 and QUIC protocol.

If you make a request to your origin web server bypassing Cloudflare - and look at your HTTP response headers, normally when i’m seeing this it is with CSP (content security policies) that have been formatted over multiple lines etc.

To make a request directly to your origin (assuming your firewall on your origin allows this) you can use curl.

curl -svo /dev/null --connect-to ::<origin_IP>

Replacing <origin_IP> with your IP address of your web server.

Alternatrively, you can update your localhost file to point to your origin IP -

You can then test in your browser and look at your network tab on your browsers developer tools to find the request that is generating this error.

Remeber your looking for the HTTP Response headers and any formatting errors.

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