I am writing a view that lists all content of a specific type. I would like to, additionally, be able to set paths to content made by a specific user. For example drupal.dd/content will give all content. Then drupal.dd/%/content will show only the content by a specific user where % is the user's name. The issue I have come across is, when I create the path with /%/content it says the first segment of the path cannot be %. I am using a contextual filter to filter by author. How would I go about doing so. I am using Drupal 8.