Nginx FAQ

net::ERR_INCOMPLETE_CHUNKED_ENCODING 200

Fixed by adding proxy_max_temp_file_size 0; in server block.

net::ERR_HTTP2_PROTOCOL_ERROR 200

The same issue as the issue ERR_INCOMPLETE_CHUNKED_ENCODING. The ERR_INCOMPLETE_CHUNKED_ENCODING happened on my server side, resource load directly from my server will be warmed as net::ERR_INCOMPLETE_CHUNKED_ENCODING 200 by chrome, and the same resource load from cloudflare will be warmed as net::ERR_HTTP2_PROTOCOL_ERROR 200. So the way to fix is the same, just adding proxy_max_temp_file_size 0; in server block.