Composerize Drupal
- update core and modules manually
- backup db & files
- create subdomain + copy there database
- on subdomain create new composer-drupal8 project
- install there all modules with exactly versions as on source web (via composer) (if some cant be installed copy them from source to modules/contrib/
- install drush
- copy missing modules from source, copy settings.php, copy sites/default/files, copy libraries (in webroot)
- change db_connect in settings.php
- try site - probably error -> run: