Issue #3029461 by gilmord, Ressinel, artem_sylchuk, manuel.adan: Move message...
requested to merge issue/private_message-3317985:private_message_phpcs_fix-33179853317985 into 3.0.x
Issue #3029461 by gilmord, Ressinel, artem_sylchuk, manuel.adan: Move message notification system to a submodule