nginx, HTTP/2, zero-length files

After an update of Centos 7.2 to 7.9 an HTTP/2-enabled vhost/site started to behave weirdly: random js/ccs files are downloaded in the browser as zero-length empty ones, but with 200 status.

I cannot reproduce this in curl using --http2 switch (seems that this has something to do with complicated browser cipher/policy algos), but this is reproducible across several client machines and browsers. Nginx reports no errors in logs. What is even more weird, is that nginx reports that body_bytes_sent isn't zero for browser requests that got zero-length files on browser side, and that length is just the same that it should be.

I realize this question looks as a "lame zero disgnostic question from guy with 1 karma" but this is really all the diagnostics what I can get. So far the workaround for me is to disable HTTP/2 in nginx. This is devastating since this is the first issue of this kind to my knowledge that I cannot ged rid of.

So... may be some of the community members has seen something similar ?