When I close a file in Lazarus and is has been modified I am asked:

File "xxx..xxx" has changed. Save?

and there are 3 buttons:

Save
Discard changes
Abort

but only the "Save" button has an underlined letter (S) which I can type on the keybord to answer.
If I want to "Discard changes" I don't know what to type because there is no underlined letter that can be typed for this answer. Neither "D" nor "N" work.
The same for "Abort" (although escape works and is quite natural).

Is this intended or a bug?