Sulu /admin/translations/sulu.en.json?v=develop error fix

Be sure you haven't deleted sulu.en.json in project web/admin, and there anything will not be deleted (for example as Vagrant's Rsync do that). After this restore translations with php bin/console sulu:translate:export .

Symfony FileType doesnt append file

If you cannot receive file on form submit (file field left null), be sure your {{ form_row(file) }} is inside {{ form-start(form) }} and {{ form_end(form) }}, and also check is this scope closed properly, check this in Devtools.

How to fix Sulu page previews

thanks to this commit, you can update Sulu from 1.6.17 to 1.6.18 and receive this fix.