Gitlab in container LXC cannot upload file


I set gitlab-ce into a LXD container , and from the main I redirect to it. The certificate from LetsEncrypt is done on the host.

So in the host , in apache I have this

 ProxyPass / nocanon
       ProxyPassReverse /
       ProxyPreserveHost On
       AllowEncodedSlashes NoDecode

SSLCertificateFile /etc/letsencrypt/live/
SSLCertificateKeyFile /etc/letsencrypt/live/

and in the LXD Container (named gitlab-example-srv), the nginx just listen on *:80

So when I try to upload a file , I have a

An error occurred while uploading the file. Please try again.

So I changed in /etc/gitlab/gitlab.rb

external_url ''
pages_external_url ""
gitlab_pages['enable'] = true
gitlab_pages['artifacts_server_url'] = '
gitlab_pages['internal_gitlab_server'] = ""
gitlab_pages['gitlab_server'] = ''

But it doesn’t work at all, in fireworks when I try to upload I still can see


It looks like the mixed content is blocked , so dropzone.js cannot be executed and so the file cannot be uploaded.

Someone has an idea how to fix it pls ?

Thank you in advance