--- a/mercurial/crecord.py	Mon Nov 02 14:26:19 2020 -0500
+++ b/mercurial/crecord.py	Sat Oct 31 17:42:31 2020 -0400
@@ -1250,7 +1250,7 @@
                 self.numstatuslines,
                 0,
                 self.yscreensize - self.numstatuslines,
-                self.xscreensize,
+                self.xscreensize - 1,
             )
         except curses.error:
             pass