Hello @Nibbler ,
I understand that you are facing an issue with your Azure Front Door Rules engine where the case transformation of the request path is not happening properly for certain URLs.
We synced offline and found that the rule you've configured right now is used to convert condition into lowercase to match condition, not transform them in action.
The to lowercase in condition is not exactly used to convert all request URLs or paths to lower case in action. It is only used to match the condition and hence it will not work for all variants of the URL.
However, you were trying to achieve transform to lowercase in action, which is a feature being worked on now by the PG team (ETA for Public Preview/GA not available yet).
Since the transform to lowercase in action feature is available in a limited private preview feature, we discussed it with the Azure WAF PG team and gathered the required information needed to get access to it.
This is a private preview feature, so it is not recommended for production at all.
NOTE: Previews are licensed to you as part of your agreement governing use of Azure, and subject to terms applicable to "Previews". An Azure feature marked “private preview” is available to specific Azure customers for evaluation purposes. This is typically by invite only and issued directly by the product team responsible for the feature or service.
You are now testing the feature to achieve your requirement.
Kindly let us know if the above helps or you need further assistance on this issue.
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