I didn't know about Alt+Up shortcut before looking into the code...
Make the context menu key operable for the HistoryTextArea. It's more common to access the context via this key.
I am not sure what key this is when I am in linux/KDE, but when I right-click in the history text field, I already see the previous strings that way. I have this "windows menu" button which doesn't seem to do anything before or after I apply this patch. But i have not tested this on any other OS yet.
ignore previous comment. it works in KDE also.