Using server 1.7.1, if I remap buttons on my USB mouse using xinput, the server doesn't process button release events in certain cases.  So, clients don't get the ButtonRelease event, and the server maintains focus on the client window because it believes a mouse button is still held down.

Specifically, the server will not process a button release for remapped button N if physical button N is currently held down.  So, if I execute:

xinput --set-button-map 'Mouse' 2 3 1

then I can press the right mouse button, press the middle, release the right, and release the middle, and get the following events, as expected:

ButtonPress event, state 0x0, button 1
ButtonPress event, state 0x100, button 3
ButtonRelease event, state 0x500, button 1
ButtonRelease event, state 0x400, button 3

But if I press the buttons in reverse order, middle then right, I only get three events:

ButtonPress event, state 0x0, button 3
ButtonPress event, state 0x400, button 1
  -- (missing event should go here) --
ButtonRelease event, state 0x500, button 1

If I later press and release the middle mouse button, I don't get a second ButtonPress for button 3, but I do get the missing ButtonRelease.

ButtonRelease event, state 0x400, button 3

This happens with both the evdev driver and the mouse driver, but it does not happen if I use xmodmap to remap the pointer buttons.