Application gateway backend path override does not work for "/"

Question

Hi

we have an Azure Application Gateway that has path-based rules and http settings with path override like described here: https://learn.microsoft.com/en-us/azure/application-gateway/configuration-http-settings

Examples:

Path mapping: /foo/*
Override: /

Expected outcome:
Accessing https://some.appgw.host/foo/bar should result in backend call like http://some.backend.host/bar

Path mapping: /foo/*
Override mapping: /bar/

Expected outcome:
Accessing https://some.appgw.host/foo/bar should result in backend call like http://some.backend.host/bar/bar

However since yesterday the first version which overrides to "/" stopped working. The backend calls preserve the path mapping. If we take the given example then the backend call looks like http://some.backend.host/foo/bar.

Is this something expected? I don't find a changelog in app gw that states such a change was made.

Update - we also realized that the URL parameters passed in the original request are stripped from the request sent to the backend.
E.g. call to https://some.appgw.host/foo/bar?param1=value1 results in backend call http://some.backend.host/foo/bar (without the parameter)

Thank you
Vasil