Attempting another fix

I am not sure about what I am doing here since I can't reproduce the CI build problem locally.

Author: odersky

compiler/src/dotty/tools/dotc/transform/ExplicitOuter.scala

@@ -96,6 +96,7 @@ class ExplicitOuter extends MiniPhase with InfoTransformer { thisPhase =>
           val parentTp = cls.denot.thisType.baseType(parentTrait)
           val outerAccImpl = newOuterAccessor(cls, parentTrait).enteredAfter(thisPhase)
           newDefs += DefDef(outerAccImpl, singleton(fixThis(outerPrefix(parentTp))))
+            .showing(i"outAcc $result, ${outerPrefix(parentTp)}")
         }
 
       val parents1 =
@@ -171,14 +172,12 @@ object ExplicitOuter {
     val outerCls = outerClass(cls)
     val prefix = owner.thisType.baseType(cls).normalizedPrefix
     val target =
-      if owner == cls then outerCls.appliedRef
-      else outerThis.baseType(outerCls).orElse(prefix.widen)
-    /*println(i"""new outer $name in $owner, $cls,
-               |prefix = $prefix,
-               |outerThis = $outerThis,
-               |outCls = $outerCls,
-               |baseType = ${outerThis.baseType(outerCls)}
-               |target = $target""")*/
+      if (owner == cls)
+        outerCls.appliedRef
+      else
+        outerThis.baseType(outerCls).orElse(
+          if prefix == NoPrefix then outerCls.typeRef.appliedTo(outerCls.typeParams.map(_ => TypeBounds.empty))
+          else prefix.widen)
     val info = if (flags.is(Method)) ExprType(target) else target
     atPhaseNoEarlier(explicitOuterPhase.next) { // outer accessors are entered at explicitOuter + 1, should not be defined before.
       newSymbol(owner, name, Synthetic | flags, info, coord = cls.coord)