Content: tags contextual filter seems to only match the first tag I have a contextual filter on the field content: tags set to "Match any value," but in practice, it appears that only nodes that match the first tag are displayed. For instance a node with the tags "blue, green" would show only other nodes tagged "blue."
It usually work better when you add a relationship to the view, where you relate the content to the taxonomy term. 
Then you unlock a whole new collection of fields and filters.

Choose to filter by taxonomy - name instead of content - tags.