In devdraw/acme, we have the ability to enter certain unicode symbols as per keyboard(7). For instance, Alt-*-m types the greek letter μ. The problem is that on X11, the patch in revision 3449 seem to break this. Rolling back to revision 3448 fixes the problem instantly.
The wrong behavior is that the shift keypress "breaks" the Alt-sequence. So if you type Alt and then KeyPress the left shift to type the *, by pressing 8, this seem to break the Alt-sequence and a * is typed. An hg blame run shows that revision 3449 changes the behavior of mouse button clicks in devdraw, so you can type other buttons by holding down alt and control. Perhaps this messes with the keyboard(7) behavior?