Hello @DG001
The Application Gateway itself does not do compression at the gateway as described in doc. However, if the backend is doing compression then it is proxied back to the user correctly.
You may vote here to request gzip compression in Azure application gateway
https://github.com/MicrosoftDocs/azure-docs/issues/23204
https://learn.microsoft.com/en-us/answers/questions/661249/enable-gzip-compression-in-azure-application-gatwa.html
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