Up until yesterday, I had my middle mouse button set up to “Show Desktop” using xbindkeys and this command pasted into the ~/.xbindkeysrc file: "wmctrl -k on" release + b:2 .
Yesterday, it stopped working. But the weird part is that it stopped working because my middle mouse (scroll) button no longer registers as an event using xev as the detection program. All other mouse buttons register in xev.
I have no idea what caused it – but I did change batteries on the device yesterday, though I think that was after this started. If it helps, it is a Logitech M325 mouse (very basic). Here is the info from Solaar on the mouse:
Path : /dev/hidraw3
Index : 1
Wireless PID : 400A
Protocol : HID++ 2.0
Polling rate : 8 ms (125Hz)
Serial : EE9D2E2A
Unit ID : 00000000
Firmware : RQM 40.01.B0018