>>> BTW, I hope we can merge some of that code directly into Emacs itself.
>> 
>> For example, marginalia--symbol-class adds new symbol characters to
>> the replacement of `help--symbol-completion-table-affixation',
>> but it would be better to add new characters directly to
>> `help--symbol-completion-table-affixation'...
>
> Yes, I would be glad if you merge back the `marginalia--symbol-class` to
> the Emacs help system! The `marginalia--symbol-class` has been inspired
> by your `help--symbol-completion-table-affixation`, but I wanted to go a
> little step further in Marginalia. Maybe it makes sense to add
> `help--symbol-class` such that the function can be reused potentially at
> other places?

Maybe something like