In plugins/decoration.c r1.19 (and a while before) in function
decorWindowUpdate() at about line 863, we have following:
/* if (dx == 0 && dy == 0) */
move = FALSE;
This setting move unconditional to false, but later on at line 884, following:
moveWindow (w, dx, dy, TRUE, TRUE);
One ot the other....
Yes, I disabled the call to moveWindow here because it didn't work correctly and
my intentions were to enable it again. However, I have now removed this dead
code as I'm not sure we'll ever enable it again.