Meta tags in Drupal 7 was super easy: With the modules Meta Tag and Meta Tags Quick you could do anything. In Drupal 8 the module meta tag covers the standard cases but meta tags quick is not available in a usable version. So what to do? As it seems there is only one flexible and easy solution: The module Context Metadata relying on the module Context.
With Context Metadata the adding of metatags for paths - as alternative to the Drupal 7 metatags quick - and other elements is super easy.
- Install and enable the modules
- Go to structure > context
- Add a context
- Add a condition to the context (for example "Request Path" for a path-based meta tag)
- Add the reaction "Context Metadata"
- Configure the meta tags