Gitlab CE 14.10.0 - 404 not found and lacking permissions after Installation - apache

Question

I've recently updated my setup from Debian 10 (Buster) to Debian 11 (Bullseye) and have Gitlab-CE installed.
I'm using Apache instead of Nginx as the system is being used as a website development server which is making use of port 80 and 443.
On my Debian 10 setup I was able to access Gitlab through a proxy / reverse proxy on a subdomain e.g. "git.example.com"
settings can be found below.
However in Debian 11 with the same configuration and setup, I am faced with an error 404 response.
Issue | Error Message
"404 : The page could not be found or you don't have permission to view it."
Image of Error Message:
https://aws1.discourse-cdn.com/business4/uploads/gitlab/original/3X/c/2/c2879ede19d693d0eb4032fd9a6a1f192bcddb97.png
Information
Notes:
System is running in Oracle Virtual Machine: Virtual Box
Example.com is used in place of my DNS / domain
Setup uses Subdomain access
GitLab has been configured with the use of Apache2 instead of Nginx
Docker is NOT being used.
Port Forwarding has been configured (Router, VM and UFW Firewall)
Image of UFW settings: https://aws1.discourse-cdn.com/business4/uploads/gitlab/original/3X/d/a/daac2a6b30f519272d7b358a4089675aab905588.png
Apache2 Modules
headers
rewrite
ssl
proxy
proxy_http
Installation
Gitlab-CE Packages
curl -s https://packages.gitlab.com/install/repositories/gitlab/gitlab-ce/script.deb.sh | sudo bash
sudo apt-get install gitlab-ce
Gitlab.rb
nano /etc/gitlab/gitlab.rb
## Set Url
external_url "https://gitlab.example.com"
## Give apache user privileges to listen to gitLab
web_server['external_users'] = ['www-data']
web_server['username'] = 'apache' # updated: apache, default: gitlab-www
web_server['group'] = 'apache' # updated: apache, default: gitlab-www
## Disable nginx
nginx['enable'] = false
## Config network
gitlab_workhorse['enable'] = true
gitlab_workhorse['listen_network'] = "tcp"
gitlab_workhorse['listen_umask'] = 0
gitlab_workhorse['listen_addr'] = "127.0.0.1:8181"
gitlab_workhorse['auth_backend'] = "http://127.0.0.1:8080"
# Puma
puma['listen'] = '127.0.0.1'
puma['port'] = 8080
Apache Http.conf
nano /etc/apache2/sites-available/http.conf
<VirtualHost *:80>
ServerName git.example.com
ServerSignature Off
RewriteEngine on
RewriteCond %{HTTPS} !=on
RewriteRule .* https://%{SERVER_NAME}%{REQUEST_URI} [NE,R,L]
</VirtualHost>
Apache Https.conf
nano /etc/apache2/sites-available/https.conf
certbot --apache
<IfModule mod_ssl.c>
<VirtualHost *:443>
# Server
ServerName git.example.com
ServerSignature Off
ProxyPreserveHost On
# Ensure that encoded slashes are not decoded but left in their encoded state.
# http://doc.gitlab.com/ce/api/projects.html#get-single-project
AllowEncodedSlashes NoDecode
<Location />
# New authorization commands for apache 2.4 and up
# http://httpd.apache.org/docs/2.4/upgrading.html#access
Require all granted
# Allow forwarding to gitlab-workhorse
ProxyPassReverse http://127.0.0.1:8181
ProxyPassReverse http://git.example.com
</Location>
# Apache equivalent of nginx try files
# http://serverfault.com/questions/290784/what-is-apaches-equivalent-of-nginxs-try-files
# http://stackoverflow.com/questions/10954516/apache2-proxypass-for-rails-app-gitlab
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,NE]
RequestHeader set X_FORWARDED_PROTO 'https'
RequestHeader set X-Forwarded-Ssl on
# Needed for downloading attachments
DocumentRoot /opt/gitlab/embedded/service/gitlab-rails/public
#Set up apache error documents, if back end goes down (i.e. 503 error) then a maintenance/deploy page is thrown up.
ErrorDocument 404 /404.html
ErrorDocument 422 /422.html
ErrorDocument 500 /500.html
ErrorDocument 502 /502.html
ErrorDocument 503 /503.html
# The default directory log is usually /var/log/httpd
# As this is an Apache2 configuration, use of ${APACHE_LOG_DIR} may be more approrpaite
LogFormat "%{X-Forwarded-For}i %l %u %t \"%r\" %>s %b" common_forwarded
ErrorLog ${APACHE_LOG_DIR}/git.example.com_error.log
CustomLog ${APACHE_LOG_DIR}/git.example.com_forwarded.log common_forwarded
CustomLog ${APACHE_LOG_DIR}/git.example.com_access.log combined env=!dontlog
CustomLog ${APACHE_LOG_DIR}/git.example.com.log combined
# SSL
# Use strong encryption ciphers only
# See ciphers(1) http://www.openssl.org/docs/apps/ciphers.html
SSLEngine on
SSLProtocol all -SSLv2
SSLHonorCipherOrder on
SSLCipherSuite "ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS"
Header add Strict-Transport-Security: "max-age=15768000;includeSubdomains"
SSLCompression Off
SSLCertificateFile /etc/letsencrypt/live/git.example.com/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/git.example.com/privkey.pem
Include /etc/letsencrypt/options-ssl-apache.conf
</VirtualHost>
</IfModule>
System & Gitlab
gitlab-rake gitlab:env:info
System: Debian 11
Current User: git
Using RVM: no
Ruby Version: 2.7.5p203
Gem Version: 3.1.4
Bundler Version:2.2.33
Rake Version: 13.0.6
Redis Version: 6.2.6
Sidekiq Version:6.4.0
Go Version: unknown
GitLab information
Version: 14.10.0
Revision: 88da5554d96
Directory: /opt/gitlab/embedded/service/gitlab-rails
DB Adapter: PostgreSQL
DB Version: 12.7
URL: https://git.example.com
HTTP Clone URL: https://git.example.com/some-group/some-project.git
SSH Clone URL: git#git.example.com:some-group/some-project.git
Using LDAP: no
Using Omniauth: yes
Omniauth Providers:
GitLab Shell
Version: 13.25.1
Repository storage paths:
- default: /var/opt/gitlab/git-data/repositories
GitLab Shell path: /opt/gitlab/embedded/service/gitlab-shell
Gitlab Status
service gitlab-runsvdir status
gitlab-runsvdir.service - GitLab Runit supervision process
Loaded: loaded (/lib/systemd/system/gitlab-runsvdir.service; enabled; vendor preset: enabled)
Active: active (running) since Sun 2022-05-01 16:48:52 BST; 40min ago
Main PID: 1786 (runsvdir)
Tasks: 304 (limit: 4915)
Memory: 2.8G
CPU: 43min 49.508s
CGroup: /system.slice/gitlab-runsvdir.service
├─1786 runsvdir -P /opt/gitlab/service log: ..............................................................>
├─1788 runsv node-exporter
├─1789 runsv grafana
├─1790 runsv gitlab-workhorse
├─1791 runsv sidekiq
├─1792 runsv gitlab-kas
├─1793 runsv puma
├─1794 runsv prometheus
├─1795 runsv redis
├─1796 runsv postgresql
├─1797 runsv postgres-exporter
├─1798 runsv logrotate
├─1799 runsv redis-exporter
├─1800 runsv alertmanager
├─1801 runsv gitlab-exporter
├─1802 runsv gitaly
├─1803 svlogd -tt /var/log/gitlab/node-exporter
├─1804 svlogd -tt /var/log/gitlab/prometheus
├─1805 svlogd /var/log/gitlab/gitlab-workhorse
├─1806 svlogd -tt /var/log/gitlab/gitlab-kas
├─1807 svlogd -tt /var/log/gitlab/puma
├─1808 svlogd -tt /var/log/gitlab/redis
├─1809 svlogd /var/log/gitlab/sidekiq
├─1810 svlogd -tt /var/log/gitlab/logrotate
├─1811 /opt/gitlab/embedded/bin/node_exporter --web.listen-address=localhost:9100 --collector.mountstats ->
├─1812 svlogd -tt /var/log/gitlab/grafana
├─1813 svlogd -tt /var/log/gitlab/gitlab-exporter
├─1814 svlogd -tt /var/log/gitlab/postgresql
├─1815 svlogd -tt /var/log/gitlab/redis-exporter
├─1816 svlogd -tt /var/log/gitlab/alertmanager
├─1817 svlogd -tt /var/log/gitlab/postgres-exporter
├─1818 svlogd /var/log/gitlab/gitaly
├─1819 /opt/gitlab/embedded/bin/prometheus --web.listen-address=localhost:9090 --storage.tsdb.path=/var/op>
├─1820 /opt/gitlab/embedded/bin/gitlab-workhorse -listenNetwork tcp -listenUmask 0 -listenAddr localhost:8>
├─1821 /opt/gitlab/embedded/bin/gitlab-kas --configuration-file /var/opt/gitlab/gitlab-kas/gitlab-kas-conf>
├─1823 /bin/sh /opt/gitlab/embedded/bin/gitlab-logrotate-wrapper
├─1824 /opt/gitlab/embedded/bin/redis-server unixsocket:/var/opt/gitlab/redis/redis.socket
├─1825 ruby /opt/gitlab/embedded/service/gitlab-rails/bin/sidekiq-cluster -e production -r /opt/gitlab/emb>
├─1833 /opt/gitlab/embedded/bin/postgres -D /var/opt/gitlab/postgresql/data
├─1834 /opt/gitlab/embedded/bin/redis_exporter --web.listen-address=localhost:9121 --redis.addr=unix:///va>
├─1835 /opt/gitlab/embedded/bin/alertmanager --web.listen-address=localhost:9093 --storage.path=/var/opt/g>
lines 1-49
Debugging
As this is system running in a VM, I've made restore points to recover the VM and rollback if necessary.
Attempts made
Change folder permissions and ownership of gitlab.rb & /opt/gitlab/embedded/service/gitlab-rails/public
Checked examples of Apache Configurations from various sources
Cleared Cache / Cookies in browser
Used other browsers to attempt loading
Tried loading Gitlab through localhost on Debian server directly "same result as accessing via git.example.com"
Updating and Upgrading packages