500 error only in chrome (works in firefox)

Solution 1:

Try inspecting the http response from the Chrome Dev tools. What kind of response do you get back from Apache?

You might also try temporarily replacing the config file of your Apache with one from scratch. That might help track down the problem.

Also check the Apache logs. You should be able to find useful information relating to the http request there.

Solution 2:

The problem was related to IPv6. I have problems to configure ipv6 with apache so I opened an other issue : Can't make a VirtualHost working with ipv6 .