Ambiguous overload detection bug

[pootow]

Compiler version

Scala ( from 3.0.0 to 3.1.2-RC1 )

Minimized code

val map = Map(
  "a" -> 1,
  "b" -> 2
)

val mapView = map.view

val optionMapView = Some(mapView)

val listOfTuples: List[(String, String)] = List(("c", "d"), ("e", "f"))

val mapViewWithDefault = optionMapView.getOrElse(Map())

val result = mapViewWithDefault ++ listOfTuples

println(result.toSeq)

Output

On scala 2, it prints List((a,1), (b,2), (c,d), (e,f)), but on scala 3, it gives a compile error:

Ambiguous overload. The overloaded alternatives of method ++ in trait IterableOps with types
 [B >: (String | Nothing, Int)](suffix: IterableOnce[B]): Iterable[B]
 [B >: (String | Nothing, Int)](suffix: IterableOnce[B]): Iterable[B]
both match arguments ((Playground.listOfTuples : List[(String, String)]))

Here is the scastie of this code snippet: https://scastie.scala-lang.org/P0gdvfw8Qg2cGnOcL0bAwg

Expectation

Compiles with no error.

[som-snytt]

Thanks for transferring from old repo, where I noted only

scala> val mapViewWithDefault = optionMapView.getOrElse(Map())
val mapViewWithDefault:
  scala.collection.MapOps[? >: String & Nothing <: String | Nothing, Int, [X0, X1] =>> scala.collection.View[(X0, X1)] | Map[X0, X1],
    scala.collection.View[(String, Int)]
   | Map[Nothing, Nothing]]
 & Iterable[(String, Int) | (Nothing, Nothing)] = MapView(<not computed>)

and workaround

scala> val mapViewWithDefault = optionMapView.getOrElse(Map.empty[String, Int])
val mapViewWithDefault:
  scala.collection.MapOps[String, Int, [X0, X1] =>> scala.collection.View[(X0, X1)] | Map[X0, X1], scala.collection.View[(String, Int)] |
    Map[String, Int]
  ]
 & Iterable[(String, Int)] = MapView(<not computed>)

scala> val result = mapViewWithDefault ++ listOfTuples
val result: Iterable[(String, Matchable)] = View(<not computed>)

[odersky]

Would be good to get a minimization that does not use the standard library.