Technowix I'm as well somehow disappointed About current stable Debian (Stock, without using external repositories) is not supported. I believed that flarum will get an awesome Forum before, but Looking on the timeline with it's progress and the huge changes from beta 7 to 8 which breaks a lot of extensions are very disappointing. Following this, Flarum seems not to become productive in the next 2 years I guess.
You guys made a great Job - for sure. But changing the core once more is very confusing and non-productive to Extension developers, even if the changes will ease up the Extension-creation. I'm currently in the process of migrating an old Forum to something new and was very excited About flarum as i found it, but now I can't follow this path, as the flarum's timeline is too far away from a productive System (there's no real Milestone schedule available as well).
I will continue to follow your development, as I like the flarum style and behaviour, but for now I can't use it as I have to keep stable Debian without external repos (PHP 7.1+).