pre 8.9 wiki pages with white space in name return a 500
Wiki pages pre 8.9 which have white space(s) in their name return a 500. New wiki pages which are created with white space(s) in their name replace the whitespace with a dash. Obviously this breaks links on pages to pages with white spaces in their name.
old: [white space](white space) directs to https://example.com/namespace/project/wikis/white%20space
newly created [white space](white space) directs to https://example.com/namespace/project/wikis/white-space