I've been looking again at unity-2d and thought I'd share a solution to bug https://bugs.launchpad.net/ubuntu/+s...2d/+bug/989477

Type the command
gksudo gedit /usr/share/unity-2d/shell/Shell.qml
Scroll down to this bit:
    PointerBarrier {
        property int x: declarativeView.globalPosition.x + (Utils.isLeftToRight() ? 0 : shell.width)
        property bool enableTrigger: launcherLoader.launcherInHideMode && launcherLoader.loadLauncher
        // This enableSticky logic has a 'bug' int RTL where the right most screen will still have enableSticky
        // set to true, but it won't cause any issue other than consuming a few bytes of mememory and calculating the 
        // rightmost x is probably more expensive and error prone than just enabling the extra barrier
        property bool enableSticky: unity2dConfiguration.stickyEdges && declarativeView.screen.geometry.x > 0

        id: leftBarrier
        triggerDirection: Utils.isLeftToRight() ? PointerBarrier.TriggerFromRight : PointerBarrier.TriggerFromLeft
        triggerZoneEnabled: enableTrigger && !launcherLoader.visibilityController.shown
        triggerOnly: enableTrigger && !enableSticky
        p1: Qt.point(x, declarativeView.screen.geometry.y)
        p2: Qt.point(x, declarativeView.screen.geometry.y + declarativeView.screen.geometry.height)
        triggerZoneP1: Qt.point(x, launcher2dConfiguration.revealMode == 1 ? declarativeView.screen.geometry.y : declarativeView.globalPosition.y)
        triggerZoneP2: Qt.point(x, launcher2dConfiguration.revealMode == 1 ? declarativeView.screen.geometry.y + 1 : declarativeView.globalPosition.y + launcherLoader.height)
        threshold: (enableSticky || enableTrigger) ? launcher2dConfiguration.edgeStopVelocity : -1
        maxVelocityMultiplier: launcher2dConfiguration.edgeResponsiveness
        decayRate: 1500
        triggerPressure: launcher2dConfiguration.edgeRevealPressure
        breakPressure: 2000

        onTriggered: launcherLoader.item.barrierTriggered()
Change the decayRate and breakPressure to the values above.

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