Issues with Grafana on selfhosted instance behind ReverseProxy

I am running Gitlab behind a reverse proxy. Unfortunately Grafana doesn't work with the Apache2 configuration in this repo.

I have a simplified version of both the http and https configurations:

Configuration port 80

<VirtualHost *:80>
  ServerName gitlab.domain.com
  ServerSignature Off
  ProxyPreserveHost On

  AllowEncodedSlashes NoDecode

  <Location />
    Require all granted

    ProxyPassReverse http://127.0.0.1:8181
    ProxyPassReverse http://domain.com/
  </Location>

  RewriteEngine on

  DocumentRoot /opt/gitlab/embedded/service/gitlab-rails/public

RewriteCond %{SERVER_NAME} =gitlab.domain.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

Configuration port 443:

<IfModule mod_ssl.c>
SSLStaplingCache shmcb:/var/run/apache2/stapling_cache(128000)
<VirtualHost *:443>
  ServerName gitlab.domain.com
  ServerSignature Off
  
  ProxyPreserveHost On

  AllowEncodedSlashes NoDecode

  <Location />
    Require all granted

    ProxyPassReverse http://127.0.0.1:8181
    ProxyPassReverse http://domain.com/
  </Location>


RequestHeader set Host "gitlab.domain.com"
RequestHeader add X-Forwarded-Ssl on
RequestHeader set X-Forwarded-Proto "https"
  RewriteEngine on

  #Forward all requests to gitlab-workhorse except existing files like error documents
  RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f [OR]
  RewriteCond %{REQUEST_URI} ^/uploads/.*
  RewriteRule .* http://127.0.0.1:8181%{REQUEST_URI} [P,QSA]
  DocumentRoot /opt/gitlab/embedded/service/gitlab-rails/public

</VirtualHost>
</IfModule>

I have tried adding these Location blocks (interchangeably):

<Location /-/grafana>
    ProxyPass http://127.0.0.1:3000
    ProxyPassReverse http://127.0.0.1:3000
</Location>

and

<Location /-/grafana>
ProxyPassReverse http://127.0.0.1:3000/
</Location>

Unfortunately I am still stuck with a 404 error page.

For more info check my issue submitted in the omnibus-gitlab repo: Here