Hello @Sergey S
You can use below PowerShell cmd to identify the apps which are using OAuth2 Implicit flow:
Pre-requisites:
- AzureAD Powershell Module
- Global Administrator or Application Administrator account credentials.
Run Connect-AzureAD and sign-in with Global Administrator or Application Administrator account.
Get-AzureADApplication | Where-Object {$_.Oauth2AllowImplicitFlow -eq "True"}
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