触摸板多点触控打开统一菜单

Question

我有一台旧的 Dell XPS 15 笔记本电脑，运行的是 Ubuntu 16.04.3。我一直遇到恼人的触摸板手势行为，例如，当我尝试滚动（2 个手指）并触摸触摸板底部时，我的统一菜单总是打开，然后它会激活光标下方的任何图标。

我想禁用它，但我不知道该怎么做。我搜索了其他人的问题，但没有找到答案。

这是我的（默认） synclient 配置：

$ synclient 
Parameter settings:
    LeftEdge                = 64
    RightEdge               = 1536
    TopEdge                 = 48
    BottomEdge              = 852
    FingerLow               = 25
    FingerHigh              = 30
    MaxTapTime              = 180
    MaxTapMove              = 80
    MaxDoubleTapTime        = 100
    SingleTapTimeout        = 180
    ClickTime               = 100
    EmulateMidButtonTime    = 75
    EmulateTwoFingerMinZ    = 282
    EmulateTwoFingerMinW    = 112
    VertScrollDelta         = 36
    HorizScrollDelta        = 36
    VertEdgeScroll          = 0
    HorizEdgeScroll         = 0
    CornerCoasting          = 0
    VertTwoFingerScroll     = 1
    HorizTwoFingerScroll    = 1
    MinSpeed                = 1
    MaxSpeed                = 1.75
    AccelFactor             = 0.108992
    TouchpadOff             = 2
    LockedDrags             = 0
    LockedDragTimeout       = 5000
    RTCornerButton          = 2
    RBCornerButton          = 3
    LTCornerButton          = 0
    LBCornerButton          = 0
    TapButton1              = 1
    TapButton2              = 3
    TapButton3              = 0
    ClickFinger1            = 1
    ClickFinger2            = 1
    ClickFinger3            = 0
    CircularScrolling       = 0
    CircScrollDelta         = 0.1
    CircScrollTrigger       = 0
    CircularPad             = 0
    PalmDetect              = 0
    PalmMinWidth            = 160
    PalmMinZ                = 200
    CoastingSpeed           = 20
    CoastingFriction        = 50
    PressureMotionMinZ      = 30
    PressureMotionMaxZ      = 160
    PressureMotionMinFactor = 1
    PressureMotionMaxFactor = 1
    ResolutionDetect        = 1
    GrabEventDevice         = 0
    TapAndDragGesture       = 1
    AreaLeftEdge            = 0
    AreaRightEdge           = 0
    AreaTopEdge             = 0
    AreaBottomEdge          = 0
    HorizHysteresis         = 9
    VertHysteresis          = 9
    ClickPad                = 0

不确定这是否有关系，但只有当我向上滚动并将手指放在触摸板的底部边缘时才会遇到这个问题。