How to install "Laravel Debugbar" in laravel 5.5?

Question

Laravel

Help please, installed laravel 5.5.
Installed "Laravel Debugbar" via Composer.
composer require barryvdh/laravel-debugbar 3.0.1
https://github.com/barryvdh/laravel-debugbar
In composer.json is "require":
:
"barryvdh/laravel-debugbar": "3.0.1",
in .env
APP_DEBUG=true
in app.php
'debug' => env('APP_DEBUG', true),
Bottom line: there is no bar on the main page and there is not even a hint of it in html.
What am I doing wrong or what else needs to be done?
I have a problem, as I already found out
[2017-09-04 12:58:16] local.ERROR: Debugbar exception: mkdir(): Permission denied
Whom only to give the right to, I did not understand.

Answer 1

Vlad Savelev ,
1) chmod -R to `~/storage`
2) chmod -R to `~/app/bootstrap`
These are two directories where the cache can be saved