PHP Deprecated:  substr(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/local/ispconfig/server/plugins-available/bind_plugin.inc.php on line 397

Fround by: PHP Deprecated:  is_dir(): Passing null to parameter #1 ($filename) of type string is deprecated in /usr/local/ispconfig/server/lib/classes/backup.inc.php on line 1311

Merge branch '6430-php8-unable-to-add-database-on-multiserver-setup-withs-eparate-db-server' into 'develop'

Resolve "PHP8: Unable to add database on multiserver setup withs eparate DB server"

Closes #6430

See merge request ispconfig/ispconfig3!1673

Unlimited quota is stored as -1, not zero, #6417

Closes #6417

See merge request ispconfig/ispconfig3!1668

Mark usage column for php sorting, #6418

Closes #6418

See merge request ispconfig/ispconfig3!1669

PHP 8 strict fixes, #6419

Closes #6419

See merge request ispconfig/ispconfig3!1670

Fixed typo. Wrong "subjectAltName" with leading dot when using self-signed certificates.

See merge request ispconfig/ispconfig3!1671

APS deletion follows symlink

See merge request ispconfig/ispconfig3!1666

Resolve "Change default URL of phpmyadmin and webmail to apps vhost"

Closes #6415

See merge request ispconfig/ispconfig3!1665

add mail_relay_domain API functions #6399

See merge request !1644

Fix var name issue crippling vhost_rewrite_v6?

Closes #6414

See merge request ispconfig/ispconfig3!1663

closes #6414

Update .gitlab-ci.yml file to account for beta releases

See merge request !1662

De lang updates

See merge request !1660

Merge branch '6411-add-ubuntu-22-04-specific-config-settings-and-version-detection-code' into 'develop'

Resolve "Add Ubuntu 22.04 specific config settings and version detection code"

Closes #6411

See merge request ispconfig/ispconfig3!1661

Resolve "Use predefined DH params file to speed-up installation"

Closes #6390

See merge request ispconfig/ispconfig3!1659

Use central predefined 4096 bit DH params file (from Mozilla https://ssl-config.mozilla.org/ffdhe4096.txt ) instead of creation one via openssl command to speed up the installation. Thank you to @ahrasis for code suggestions.