Drupal 8, by default, does not allow non-registered users to leave comments. If you want to allow visitors to be able to leave comments on your site, follow the instructions below.
How to give visitors commenting privileges
- Log into your Drupal 8 admin interface.
- Look to the top menu bar on the page and click on the Menu tab.
- A second menu bar will appear. Click on the People option to continue.
- Now we are on the People where it lists the site members. Click on the Permissions tab in the upper right corner.
- This leads you to the master Permissions list. Look for the Comment section and locate the Post Comments permission. Click on the checkbox for the Anonymous User column.
- Once you have selected the checkbox, click on the Save Permissions button at the bottom. This will enable the non-registered visitor to leave comments on your site. Below you can see a shot of a post both before the permission is active and after.