Why some font-awesome icons are not rendered - laravel-5

Question

In my laravel 5.7 / Bootstrap 4.1 app
I installed font-awesome package with command
npm install font-awesome --save
and in my package.json I have :
"dependencies": {
...
"font-awesome": "^4.7.0",
...
}
In webpack.mix.js there is line :
mix.copy('node_modules/font-awesome/fonts', 'public/fonts');
In fonts directory I see
nick#nick:project/public/fonts$ ls -la
total 1080
drwxrwxrwx 1 root root 4096 лис 9 14:32 .
drwxrwxrwx 1 root root 4096 лис 6 06:04 ..
-rwxrwxrwx 1 root root 134808 лис 9 14:32 FontAwesome.otf
-rwxrwxrwx 1 root root 165742 лис 9 14:32 fontawesome-webfont.eot
-rwxrwxrwx 1 root root 444379 лис 9 14:32 fontawesome-webfont.svg
-rwxrwxrwx 1 root root 165548 лис 9 14:32 fontawesome-webfont.ttf
-rwxrwxrwx 1 root root 98024 лис 9 14:32 fontawesome-webfont.woff
-rwxrwxrwx 1 root root 77160 лис 9 14:32 fontawesome-webfont.woff2
drwxrwxrwx 1 root root 4096 лис 7 10:16 roboto
drwxrwxrwx 1 root root 0 лип 22 08:07 vendor
The problem is when I try to use these icons, not all of them are rendered.
Say icons fa fa-alicorn or fa fa-air-freshener are empty.
I select icon from this https://fontawesome.com/icons?d=gallery&q=freshener selector.
You can check it by http://votes.nilov-sergey-demo-apps.tk/admin/dashboard url, under "Icons Samples" block there some some icons
which are visible, but some not.
Why? Are these different version of icons in my app?
Thanks!

Answer 1

The icons that are not displaying are not available in your fontawesome version. You are using fontawesome v4, the missing icons are only available in fontawesome v5.
Here you can find all icons available for v4:
Here you can find the install guide for v5.