Hello @Tammy Tran ,
Apologies for the delay in response.
If I understand correctly, you have enabled custom domain for Azure AD B2C by using Azure Front Door and would like to know how AFD will accelerate the application performance.
To answer your query - By default, any traffic which flows through Azure Front Door is accelerated.
Kindly let us know if the above helps or you need further assistance on this issue.
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