[PLUG] Trackball middle button pastes string twice

[Rich Shepard]

   This behavior started over the weekend and is quite annoying. When I press
the two small buttons on the Logictech Marble trackball (emulating the
middle button on a 3-button mouse in 10-evdev.conf) the highlighted string
is inserted twice.

   Web searches find only a couple of results specific to linux, one
apparently related to a tool on Arch, the other with xfce4 that had a second
post by the thread offer noting the problem was the mouse. Neither had
useful information for me. Most other results asked how to disable pasting
with the middle mouse button.

   I welcome any and all suggestions on identifying the source of this
behavior.

Rich