These 2 patches fix issues with system clipboard interfacing in the x11 terminal:
There was an off-by-one error so sometimes there was an extra character that would be pasted. This would happen if you double-click with a long-string clipboard mode, and then do it again with a shorter one. A character from the previous paste string would fall through.
Gnuplot was clearing out the clipboard with each paste. So client applications could one paste once.