Symlinked plugin directory doesn’t appear in Admin

I have a simple test plugin – a folder called tester containing a file called tester.php that contains only this:

<?php
/*
Plugin Name: My tester
*/
?>

I have a copy of WordPress running locally on my Mac. When the plugin is in the plugins directory it appears in the Admin list of plugins.

When I move the plugin directory elsewhere and symlink to it, it doesn’t show up.

I’ve done similar with a theme, and WordPress happily uses that. From what I’ve read this should now work with plugins too. Am I missing something?

(WordPress 4.8)

What have you done to add the symlink?

In using VVV I am able to symlink using your plugin tester code:

    # ssh into vagrant
    $ vagrant ssh
    # create symlink
    $ sudo ln -s /srv/www/wordpress-default/wp-content/testing-dir/tester /srv/www/wordpress-default/wp-content/plugins/tester