Related content in Drupal 8

We will need to use 2 contextual filters. Id and Has taxonomy term id.

Configure Id filter as following:

• Provide default value: Content ID from URL
• Under More tab - Check next to Exclude

Configure Has taxonomy term id as following:

• Provide default value: Taxonomy term ID from URL
• Uncheck: Load default filter from term page
• Check next to: Load default filter from node page, that's good for related taxonomy block
• Multiple value handling: Filter to items that share any value
• Check next to Reduce Duplicates
• Under more tab check: Allow multiple values and Allow multiple values to work together.