Enable or disables the IE11OptOut Feature for a SPO site collection

Enable-IE11OptOutSPOFeature.ps1

Add-Type -Path "C:\Microsoft.SharePointOnline.CSOM.16.1.6008.1200\lib\net45\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Microsoft.SharePointOnline.CSOM.16.1.6008.1200\lib\net45\Microsoft.SharePoint.Client.Runtime.dll"
[System.Net.WebRequest]::DefaultWebProxy.Credentials = [System.Net.CredentialCache]::DefaultCredentials 

function Enable-SPOFeature
{
    [cmdletbinding()]
    param
    (
        [parameter(Mandatory=$true)][Microsoft.SharePoint.Client.ClientContext]$ClientContext,
        [parameter(Mandatory=$true)][System.Guid]$FeatureID,
        [parameter(Mandatory=$false)][ValidateSet("Site","Web")]$Scope,
        [parameter(Mandatory=$false)][Switch]$Force
    )

    begin
    {
    }
    process
    {
        Write-Verbose "Activating Feature '$FeatureID' at scope $Scope on $($ClientContext.Url)"
        
        switch( $scope )
        {
           "Web"
           {
                $feature = $ClientContext.Web.Features.Add($FeatureID, $Force.IsPresent, [Microsoft.SharePoint.Client.FeatureDefinitionScope]::Farm)
           }
           "Site"
           {
                $feature = $ClientContext.Site.Features.Add($FeatureID, $Force.IsPresent, [Microsoft.SharePoint.Client.FeatureDefinitionScope]::Farm)
           }
        }

        try
        {
            $ClientContext.ExecuteQuery()
            Write-Verbose "Feature Activation for '$FeatureID' at scope $Scope on $($ClientContext.Url) succeeded."
            return $true
        }
        catch
        {
            Write-Error "Feature Activation for '$FeatureID' at scope $Scope on $($ClientContext.Url) failed. Error: $_"
            return $false
        }
    }
    end
    {
    }
}

function Disable-SPOFeature
{
    [cmdletbinding()]
    param
    (
        [parameter(Mandatory=$true)][Microsoft.SharePoint.Client.ClientContext]$ClientContext,
        [parameter(Mandatory=$true)][System.Guid]$FeatureID,
        [parameter(Mandatory=$false)][ValidateSet("Site","Web")]$Scope,
        [parameter(Mandatory=$false)][Switch]$Force
    )

    begin
    {
    }
    process
    {
        Write-Verbose "Activating Feature '$FeatureID' at scope $Scope on $($ClientContext.Url)"
        
        switch( $scope )
        {
           "Web"
           {
                $feature = $ClientContext.Web.Features.Remove( $FeatureID, $Force.IsPresent )
           }
           "Site"
           {
                $feature = $ClientContext.Site.Features.Remove( $FeatureID, $Force.IsPresent )
           }
        }

        try
        {
            $ClientContext.ExecuteQuery()
            Write-Verbose "Feature Deactivation for '$FeatureID' at scope $Scope on $($ClientContext.Url) succeeded."
            return $true
        }
        catch
        {
            Write-Host "Feature Deactivation for '$FeatureID' at scope $Scope on $($ClientContext.Url) failed. Error: $_"
            return $false
        }
    }
    end
    {
    }
}

if( -not $credential )
{
    $credential = Get-Credential 
}

$siteUrl = "https://contoso.sharepoint.com/sites/teamsite"

$clientContext = New-Object Microsoft.SharePoint.Client.ClientContext($siteUrl)
$clientContext.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($credential.UserName, $credential.Password)

# Enable-SPOFeature -ClientContext $clientContext -FeatureID "80E47777-D21C-46E0-9139-7C7741EB4B54" -Scope Site

# Disable-SPOFeature -ClientContext $clientContext -FeatureID "80E47777-D21C-46E0-9139-7C7741EB4B54" -Scope Site