How to Deactivate a SharePoint Feature without Prompt using PowerShell

  1. Disable-SPFeature -identity $featureName   
  The above script will deactivate feature in farm level. 
  1. Disable-SPFeature -identity $featureName -URL $siteURL  
The above script will deactivate feature in sitecollection or site level based on the URL provided.
 
But in both the cases while running the script it will prompt an Confirm alert.
 
Confirm

Are you sure you want to perform this action?

Performing operation "Disable-SPFeature" on Target "Farm Scope |ff48f7e6-2fa1-428d-9a15-ab154762043d".
[Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help (default is "Y"):
 
To avoid the above confirm alert Run the below script to deactivate the feature without confirm alert. 
  1. Disable-SPFeature -identity $featureName -URL $SiteURL -Confirm:$false  
Now the feature will be deactivated without any prompt.