MessageBox button results became "String" in 0.8.3

Before 8.3.0, the result of ShowDialog() was a "MessageBoxResult" Enum type, that is convenient to check which button was pressed by the user in relation to the set of showed buttons (passed as parameter using "MessageBoxButtons" Enum).

After 8.3.0... the output is now a "String" that contains the text of the pressed button.

I think it is way more convenient and code-clear to continue using Enums, instead of doing string comparison. Why has it changed?