API: improve dtype in df.where with EA other

Author: jbrockmendel

doc/source/whatsnew/v3.0.0.rst

@@ -97,7 +97,7 @@ Other enhancements
 - Support passing a :class:`Iterable[Hashable]` input to :meth:`DataFrame.drop_duplicates` (:issue:`59237`)
 - Support reading Stata 102-format (Stata 1) dta files (:issue:`58978`)
 - Support reading Stata 110-format (Stata 7) dta files (:issue:`47176`)
-
+- Improve the resulting dtypes in :meth:`DataFrame.where` and :meth:`DataFrame.mask` with :class:`ExtensionDtype` ``other`` (:issue:`??`)
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 .. _whatsnew_300.notable_bug_fixes: