turns off when you move your mouse

mouse-jiggle-keyboard-stroke-minfiied.ps1

Add-Type -assemblyName System.Windows.Forms;$a=@(1..100);$chars="abc";while($true){$c=[System.Windows.Forms.Cursor]::Position;Start-Sleep -Seconds 5;if($c -eq $([System.Windows.Forms.Cursor]::Position)){$randomX=$a|Get-Random;$randomY=$a|Get-Random;$newPosition=New-Object System.Drawing.Point($randomX,$randomY);[System.Windows.Forms.Cursor]::Position=$newPosition;$randomChar=($chars.ToCharArray()|Get-Random -Count $chars.Length)-join"";[System.Windows.Forms.SendKeys]::SendWait($randomChar);$backspaces="{0}"-f('{BACKSPACE}'*$randomChar.Length);[System.Windows.Forms.SendKeys]::SendWait($backspaces)}}

mouse-jiggle-keyboard-stroke.ps1

Add-Type -assemblyName System.Windows.Forms

$a = @(1..100)
$chars = "abc"

while ($true) {
    $c = [System.Windows.Forms.Cursor]::Position
    Start-Sleep -Seconds 5

    if ($c -eq $([System.Windows.Forms.Cursor]::Position)) {
        $randomX = $a | Get-Random
        $randomY = $a | Get-Random
        $newPosition = New-Object System.Drawing.Point($randomX, $randomY)

        [System.Windows.Forms.Cursor]::Position = $newPosition

        # Randomize the order of $chars, meaning: "abc" or "bac" or "cab" etc.
        $randomChar = ($chars.ToCharArray() | Get-Random -Count $chars.Length) -join ""
        [System.Windows.Forms.SendKeys]::SendWait($randomChar)

        $backspaces = "{0}" -f ('{BACKSPACE}' * $randomChar.Length)
        [System.Windows.Forms.SendKeys]::SendWait($backspaces)
    }
}

mouse-jiggle-minified.ps1

Add-Type -assemblyName System.Windows.Forms;$a=@(1..100);while(1){$c=[System.Windows.Forms.Cursor]::Position;start-sleep -seconds 5;if ($c -eq $([System.Windows.Forms.Cursor]::Position)) {[System.Windows.Forms.Cursor]::Position=New-Object System.Drawing.Point(($a|get-random),($a|get-random))}}

mouse-jiggle.ps1

Add-Type -assemblyName System.Windows.Forms

$a = @(1..100)

while ($true) {
    $c = [System.Windows.Forms.Cursor]::Position
    Start-Sleep -Seconds 5

    if ($c -eq $([System.Windows.Forms.Cursor]::Position)) {
        $randomX = $a | Get-Random
        $randomY = $a | Get-Random
        $newPosition = New-Object System.Drawing.Point($randomX, $randomY)

        [System.Windows.Forms.Cursor]::Position = $newPosition
    }
}