In joe 3.1 there's a bug with the quick selection method (Ctrl+arrows) when
the selection is finished at the very beginning or very end of the file.
The bug does not occur always, but very often (say, 90% of cases).
Open a text file, go near its end, and press Ctrl+Downarrow to reach the
end. Then release Ctrl. If you move the cursor with the arrows, you'll see
the end of the selection still changing, though it shouldn't. Similarly:
start the selection somewhere near the beginning of the file and go to its
very beginning by pressing Ctrl+Up. Usually it is stuck in selection mode
after releasing Ctrl.
Why this bug is more irritating is because I first faced this in multi
window mode. Highlight the first or last few lines of a text file in the way
described above and then switch to the other window with ^KN. Visually
everything seems to be alright, the selected text is highlighted, however,
^KC, instead of copying the block, gives a "No block" error.