Anonymous dot notation fails on propositions defined by ∀

[YaelDillies]

Prerequisites

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Description

def Foo : Prop := ∀ a : Nat, a = a

protected theorem Foo.intro : Foo := sorry
example : Foo := .intro

produces

invalid dotted identifier notation, unknown identifier `Eq.intro` from expected type
  Foo

on the example

Expected behavior: Anonymous dot notation works here

Actual behavior: Anonymous dot notation doesn't work here

Context

In Mathlib, anonymous dot notation on Monotone fails due to this bug. See eg leanprover-community/mathlib4#13338 (comment).

Versions

4.10.0-rc2

Impact

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