IntelliSense reports different number of overloads than signature help

[Suchiman]

Version Used: VS 15.5.2

Steps to Reproduce:

1. Go to this line of code

   roslyn/src/Compilers/Core/Portable/PEWriter/UsedNamespaceOrType.cs

   Line 61 in b0bd4af

   return obj is UsedNamespaceOrType && base.Equals((UsedNamespaceOrType)obj);

2. Hover base.Equals and Quick Info suggests there's one additional overload
   
3. Prompt Signature Info and it only shows one overload
   

Expected Behavior:
When Quick Info displays (+1 overload) then Signature Info should show exactly 2 overloads

Actual Behavior:
Signature Info may show less overloads than Quick Info suggests there are.

[sharwell]

Duplicate of #22341

This seems to be a slightly different cause, but very similar to the above bug.

[Suchiman]

@sharwell at least in the same direction, i believe the bug here is with Quick Info and Signature Info is correct, i'm not sure where Quick Info is getting that additional overload from... perhaps the static object.Equals(Object objA, Object objB)
Even if you clear it to base.Equals() Signature Info still shows only one overload.