[visual studio] installer 'install'/'uninstall' not available

Try to "build"/"Rebuild" installer project in solution.

symfony 404 not found on file upload

be sure you changed "upload_max_size" in needed php.ini, added "client_max_body_size 100m;" in case nginx.conf, and do not forget to restart all php, nginx, apache2 daemons, or better reboot system.

twig unrecognized field 0

because you forget add parameter as associated array, for example

findOneBy(['providerReference' => $reference])

, not (['provideReference', $reference])

[Symfony] [ckeditor] browse / upload buttons missing - how to fix

be sure you don't have duplicate call of ivory_ck_editor in config.yml file.

composer & php 5.6.26 & ubuntu: curl is missing from your system

sudo apt-get install php5.6-curl
sudo a2enmod proxy_fcgi setenvif
sudo a2enconf php5.6-fpm
sudo service apache2 reload

helped notices from php5.6-cur installing

Dr Web blocked my HOSTS file, how to fix?

Just reboot system and have access to read/write in it

symfony fixtures cannot delete or update a parent row

* you can add to problem entity field, which is described in error onDelete="set null"

* or deny to purge your database, add to your command key --append.