*rb files not generating

[emilhakobian]

After adding Capistrano Environment *.rb file not creating. Also there is no "Deploy Config" textarea.
Even if I create those *.rb files manually textarea does not appear.
Folder permmissions are writable for server user (www-data or nginx). See attached screenshot.

[swilsonau]

Adding the following to your mysite/_config/config.yml:

DNEnvironment:
 allow_web_editing: true

Will enable that functionality. Not sure why it isn't enabled by default.