Disappearing mouse buttons

[Tom Ivar Helbekkmo <tih%hamartun.priv.no@localhost>]

I'm looking for something that I can't find...  The "Kensington Expert
Mouse" trackball on my amd64-current workstation has four buttons and a
scroll wheel, and these used to generate all different button presses -
so at least six distinct buttons.  This was still working with a
-current from back at the start of September.

After a fresh update, however, it now reports thus:

uhidev1 at uhub4 port 1 configuration 1 interface 0
uhidev1: vendor 047d (0x047d) Kensington Expert Mouse (0x1020), rev 2.00/1.06, addr 4, iclass 3/1
ums0 at uhidev1: 5 buttons and Z dir
wsmouse0 at ums0 mux 0

With this, I suddenly have the fourth button mapped as a duplicate of
one of the scroll wheel directions.  The wsmouse mapping is "1 2 3 4 5",
and the fourth button generates button 4; the scroll wheel 4 and 5.  The
fourth button, then, is just single steps of one scroll direction, while
it used to give me the "back" function normally associated with one of
the thumb buttons on most modern mice.

I've been looking at changes in sys/dev/usb, sys/dev/hid, and
sys/dev/wscons, but I can't find anything that looks relevant.

If anyone has any hints for me, that would be appreciated!

-tih
-- 
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