Creating a slot using Resource Explorer

This applies to both Web App and Function Apps.

First, create a regular App using the Portal
Go to https://resources.azure.com/
Find your site in the tree or using the search box
In the json for the site, capture the location (e.g. 'North Central US') and the serverFarmId (long ARM resource name).
Under the site, click on the 'slots' node (you don't have any yet)
Click on the Create tab
Set the name to Staging (or whatever you want to call the slot)
Set both the location and the serverFarmId to the same values that you saw earlier
Click the PUT button at the top. You're done, you have a slot!

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