Hi, I'm using nginx as a reverse proxy and found a behavior that I wouldn't expect.

According to some references below, I assume nginx would downgrade strong etags to weak ones when it modifies response content (e.g. gzip compression). But nginx removes strong etags on gzip compression instead of a downgrade.

- http://nginx.org/en/CHANGES (See "Changes with nginx 1.7.3 08 Jul 2014")
- > *) Feature: weak entity tags are now preserved on response modifications, and strong ones are changed to weak.
- https://github.com/nginx/nginx/commit/def16742a1ec22ece8279185eb2b798eb5ffa031
- > Entity tags: downgrade strong etags to weak ones as needed.

I created a gist to reproduce the behavior with minimum requirements, please see https://gist.github.com/ohbarye/86f2d5b464f5e88821133c43a9cf4956

So my question is: Is it expected behavior that nginx removes strong etags on gzip compression?

Regards