ApplicativeDo failed to desugar last line with pure $ <expr>

{-# LANGUAGE ApplicativeDo #-}
f m = do
  x <- m 1
  y <- m 2
  return $ x + y

f should have type (Applicative f, Num a, Num b) => (a -> f b) -> f b but ghc considers f a monad

maybe similar with #11607 (closed)

Trac metadata

Trac field	Value
Version	8.0.1-rc2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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