This bug was fixed in the package unity - 7.4.5+16.04.20171201.3

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unity (7.4.5+16.04.20171201.3) xenial; urgency=medium

  [ Marco Trevisan (Treviño) ]
  * InputMonitor: add an unity class that monitors XInput2 events and
    converts them to XEvent
  * EdgeBarrierController: use InputMonitor to get the barrier events
    instead of relying on its implementation
  * DecorationsMenuLayout: use input monitor for menu scrubbing (LP:
    #1614597)
  * PanelView: use InputMonitor to track menu events
  * LockScreenPanel: use InputMonitor events instead of mouse polling
    for menu scrubbing
  * MenuManager: add support for mouse trackers with triangle algorithm
    support (LP: #1618405)
  * PanelView: scale gradient refinement properly
  * PanelService: don't allow to deactivate menus if they've been opened
    too shortly
  * LockScreenController: ignore icon_paths_changed signal in
    menumanager for Lockscreen
  * LockScreenController: use InputMonitor to get all the events and
    hide the Blank Window (LP: #1321075)
  * LockScreenController: use input monitor to get the events to switch
    monitor (LP: #1316862)
  * LauncherOptions: use track_obj to manage option changes (LP:
    #1622995)
  * UnityScreen: toggle gestures recognition on lock (LP: #1645507)
  * GnomeSessionManager: add gcancellable to instance and use it for
    calls with temporary proxies
  * BackgroundSettings: use gnome-bg to generate textures with proper
    scaling (LP: #1666359)
  * UnityWindow: safely check validity of UnityWindow from scaled one
    (LP: #1659847)
  * Panel: ensure the menu-manager tracker is updated to match monitor
    (LP: #1671432)
  * compiz-profile-setter: tool to update the current profile and use in
    systemd and Unity settings (LP: #1668950)
  * BGHash, UnityScreen: get desktop averageColor from compiz
  * Launcher: disable or reduce most icon effects on lowgfx (LP:
    #1700859)
  * PanelController: ensure we disconnect from signals on destruction
    (LP: #1504870)
  * tools: add migration script to set the default values for unity-
    lowgfx profile

  [ Andrea Azzarone ]
  * Properly handle the file manager copy dialog in
    FileManagerLauncherIcon and in StorageLauncherIcon. (LP: #1575452,
    LP: #1609845)
  * Correctly position the force quit dialog when scaling is different
    than 1.0 (LP: #1637991)
  * GnomeSession: Retrieve the session id using dbus if $XDG_SESSION_ID
    is not set
  * Round gtk scaling factor to closest integer. (LP: #1649736)
  * Keep the screen locked if rebooting with autologin. (LP: #1600389)
  * Use g_mkdir_with_parents instead of mkdir.
  * Lockscreen: always draw the background-color in the lockscreen (LP:
    #1702701)
  * Refactor the way UserAuthenticator is created and passed around.
    Handle failures to create new threads and fallback to a "Switch to
    greeter..." button in case of failure. (LP: #1311316)
  * Wait until the color buffer is cleared before suspending. (LP:
    #1532508)

  [ Kai-Heng Feng ]
  * UnitySettings: If scale-factor is not set, find and set right scale
    for HiDPI displays.

  [ Eleni Maria Stea ]
  * shouldn't create blur rectangles when there's no blur, skips the
    blur rects processing in low gfx.
  * removes lowgfx option from ccsm, reads the "lowgfx" gsetting (LP:
    #1668950)

  [ Nick Dedekind ]
  * Fixed tooltip scaling issues. (LP: #1673950)

 -- Marco Trevisan (Treviño) <mail@3v1n0.net>  Fri, 01 Dec 2017 18:46:01 +0000