Using a clean install of Ubuntu 15.10 with Parallels Pro 11, each time window spread is supposed to happen, X crashes(?). Also alt-tab is not working at all (maybe related, as it has window spread'ish features?). For example, having two Firefox windows, you're unable to select other one, except right clicking the icon and selecting the other window from the menu. Alt-tab missing is also a serious annoyance. X.org log is full of stuff like this upon this happening: [ 4051.126] (II) PRLCONTROL: Window manager lost [ 4051.129] (II) PRLCONTROL: Window manager detected [ 4051.159] (II) PRLCONTROL: Composite overlay window (DrawablePtr=0x55bd42b0f800) detected [ 4051.233] (II) PRLCONTROL: GL PBuffer(this=0x55bd4492a860, host_pbuf=56779043, glxId=8000DD, drawId=67, GLXDrawablePtr=0x55bd3ebd9370, DrawablePtr=0x55bd42b0f800, tex_fmt=20DA, tex_tgt=20DD) created [ 4051.233] (II) PRLCONTROL: OpenGL Composite overlay detected (drawId=67, DrawablePtr=0x55bd42b0f800, glxId=8000DD, GLXDrawablePtr=0x55bd3ebd9370). [ 4051.233] (II) PRLCONTROL: OpenGL Compositing enabled. [ 4051.839] (II) XKB: reuse xkmfile /var/lib/xkb/server-512EBCD68AC1E2FA60C22C350CABFE45CED6DB75.xkm [ 4051.842] (II) PRLCONTROL: Coherence plugin enabled (pid=31403 userid=3E8) [ 4051.853] (II) PRLCONTROL: Window manager lost [ 4051.853] (II) PRLCONTROL: Window manager detected [ 4051.860] (II) PRLCONTROL: Window manager lost [ 4051.860] (II) PRLCONTROL: Window manager detected [ 4051.873] (II) PRLCONTROL: Window manager lost [ 4051.873] (II) PRLCONTROL: Window manager detected [ 4051.877] (II) PRLCONTROL: Window manager lost [ 4051.877] (II) PRLCONTROL: Window manager detected [ 4051.880] (II) PRLCONTROL: Window manager lost [ 4051.881] (II) PRLCONTROL: Window manager detected
