https://rubyapi.org/2.7/o/tempfile

The parent class there links to https://rubyapi.org/2.7/o/delegateclass(file), which 404s.

The ruby-doc page for Tempfile also lists DelegateClass(File) as the parent class, but it's not a link.
https://ruby-doc.org/stdlib-2.7.1/libdoc/tempfile/rdoc/Tempfile.html