Fn/FnMut template parameters

Editors and IDEs
2

I thought this might be a dupe of Rust-analyzer autocompletes functions with an ellipsis instead of parameters but it's not, even setting

analyzer.completion.fullFunctionSignatures.enable to true as per the user manual, like so in emacs...

  (add-to-list 'eglot-server-programs
               '((rust-ts-mode rust-mode) .
                 ("rust-analyzer"
                  :initializationOptions
                  (:checkOnSave :json-false
                   :diagnostics (:enable :json-false)
                   :completion (:fullFunctionSignatures (:enable 't))))))

only enables

Whether to show full function/method signatures in completion docs.

but not for method completions.