Views default_argument plugin to use values from the current page entity as default values for a contextual filter. Similar what the "Content ID from URL" default value is doing, except you can pull any field value from that content instead of just the ID (but also you're not limited only to nodes, all entity types are supported). A simple example would be to use the tags from the current page node to feed a "similar content" block. Works for any content entity type as long as the entity is accessible as a route parameter using the entity type id as the route parameter name (i.e.