[register] Delay post-ime reset of the selection.

Works around bug 798587.

gnucash/register/register-gnome/gnucash-sheet.c

@@ -1833,6 +1833,11 @@ gnucash_sheet_key_press_event_internal (GtkWidget *widget, GdkEventKey *event)
     /* Followed by the input method */
     if (gtk_entry_im_context_filter_keypress (GTK_ENTRY(sheet->entry), event))
     {
+        /* There's sometimes a timing issue when running under KDE
+         * Plasma where this call removes the selection. This 1ms
+         * sleep prevents it.
+         */
+        usleep(1000);
         /* Restore the saved cursor position in case GtkEntry's IMContext
          * handlers messed with it after we set it in our insert_cb.
          */