This test requires a site which allows plugins to be installed from within the site. The site registration should be edited and an older Moodle version specified in order to get an Install button to display in step 3. (The QA testing site cannot be used for this test, since plugin installation is disabled.)

1. Login as an admin and go to Administration > Site administration > Plugins > Install plugins.
2. Click the button 'Install plugin from Moodle plugins directory'.
3. Choose a plugin with an Install button, such as codechecker (https://moodle.org/plugins/local_codechecker), click the Install button then click Continue.
4. Check that you obtain a 'Validation passed!' message, then click the button 'Install plugin'.
5. Check that the plugin is installed successfully and appears in the list Administration > Site administration > Plugins > Plugins overview
6. Try uninstalling the newly installed plugin by clicking the Uninstall link opposite the plugin
7. Use a file manager to remove/delete the actual plugin directory as instructed
8. Check that the plugin is no longer listed on Administration > Site administration > Plugins > Plugins overview.