Disable SharePoint App Bar using PowerShell
Steps to disable SharePoint App Bar. Read my blog post for details:
https://m365worldblog.com/disable-sharepoint-app-bar-using-powershell/
Open SharePoint Online Management Shell and use below commands:
#Connecting to SharePoint Online PowerShell Module
Connect-SPOService -URL https://o365premier-admin.sharepoint.com
#Temporarily disable SharePoint App Bar
Set-SPOTemporarilyDisableAppBar $true
#To check the state of SharePoint App Bar
Get-SPOTemporarilyDisableAppBar