To activate the admintoolbar in front office the backend user must be logged in and the config/environment.php must define the host as dev env
return [
/*
|--------------------------------------------------------------------------
| Environment Multitenancy
|--------------------------------------------------------------------------
|
| You may specify a different environment according to the hostname that
| is provided with the HTTP request. This is useful if you want to use
| different configuration, such as database and theme, per hostname.
|
*/
'hosts' => [
'your.dev.domain' => 'dev',
],
];