Javascript file not load finish and timeout CAUTION: request is not finished yet! (When active Proxied)

[p.kasidits]

When Proxied on my Javascript file cannot load finished.
I looking in developer console and got this message “CAUTION: request is not finished yet!”
then the request status was timeout after that show err_quic_protocol_error.

Any one got this issue and how to slove it?
Thank you in advance

[p.kasidits]

As of my investigation, Look like this problem just occure when cloudflare don’t have cached on that file. So Cloudflare must load that file from origin server. after load completed Cloudflare does not sent that result to client.

After second refresh that file can responsed (My view is cloudflare already cached that it from the first request)

So, As I understand this this is the issue on cloudflare site.

Note: This ploblem got only the “proxied” on.

How to slove this issue, please advice.
Thanks

[p.kasidits]

For more infomation.
When I use curl the result show error as below.

HTTP/2 stream 0 was not closed cleanly: INTERNAL_ERROR (err 2)