Hi @Rafael Silva,
Updates are normally posted on https://azure.microsoft.com/en-us/updates/?. You may also find some updates posted under https://azure.microsoft.com/en-us/blog/ as well. But it's unlikely that small UI tweaks will be posted though. For the overview of the function, it may not be under Overview tab at the function app level, but the information should still be available by clicking the function name under the Overview blade of the function app. Basically, just relocated.
As for Cosmos, Diagnostic settings is still there under Monitoring. Since your access is Reader role, I would verify the access you have either at the resource level or resource group. You do this by selecting the View My Access button under Access control (IAM) blade.
If you're referring to a different screen or specific information, please do let me know down below.
EDIT 2024 May 23
Per our offline conversation, I wanted to update my answer to better benefit the community. We did determine the JSON View link had been removed when the Function blade experience was revised. Unfortunately, there isn't a workaround for that capability other than using az functionapp list --resource-group myResourceGroup --name myFunctionApp
. However, I have raised this feedback with the team.