Can't create simple CakePHP plugin - cakephp

Question

I would like to create a plugin for CakePHP 3.1.4. The documentation is straight forward, but the example doesn't work (http://book.cakephp.org/3.0/en/plugins.html#creating-your-own-plugins)
The steps are:
composer create-project --prefer-dist cakephp/app sampleapp
Create the database. Connect to the database. Create a table "contacts". Navigate in the directory and run:
bin/cake bake plugin ContactManager
Create the controller:
bin/cake bake controller --plugin ContactManager Contacts
Re-generate the autoloader:
composer dumpautoload
Add this line to the /config/bootstrap.php file:
Plugin::load('ContactManager', ['routes' => true]);
But now, the documentation sais
"If you want to access what we’ve got going thus far, visit
/contact-manager/contacts. You should get a “Missing Model” error
because we don’t have a Contact model defined yet."
But this doesn't work. Instead I get an error:
Missing Controller.
Cake\Routing\Exception\MissingControllerException.
Cake\Routing\Dispatcher->dispatch ROOT/webroot/index.php, line 37
Error: ContactManagerController could not be found. Error: Create the
class ContactManagerController below in file:
src/Controller/ContactManagerController.php
This means the plugin could not be loaded otherwise it would not suggest this. When opening the DebugKit under "Include" the plugin is not in the plugins array.
I checked the composer.json files and in both the plugin is listed correctly. The bake command ran through without errors. I tried the above steps with multiple new projects with different names.
What is the problem here? Thank you very much.

Answer 1

Finally, I found the solution.
What the docs say should be in /plugins/ContactManager/config/routes.php AND what bake plugin creates:
Router::plugin('ContactManager', function ($routes) {
$routes->fallbacks('DashedRoute');
});
But what really needs to be in the file instead of the above snippet is:
Router::scope('/contactmanager', ['plugin' => 'ContactManager'], function ($routes) {
$routes->fallbacks();
});