See https://en.wikipedia.org/wiki/User:Whatamidoing_(WMF)/sandbox?veaction=edit§ion=1
This is the simplest possible blockquote, and it works around the limitations described in T86794: <blockquote> tags on different line from content of blockquote results alienated content. This should be editable (indeed, this blockquote was originally created in the visual editor), and it's not.