I have a Polkadot.JS App extension and it also pops up when I connect to the Sporran. Do I need to allow both apps access?

No, you can choose which app to give access to. If you wish to use the Sporran you can disable the Polkadot.JS popup:

1. Go to Settings in the Polkadot.JS App (top right, cog icon)

2. Scroll to "Manage Website Access"

3. Scroll to stakeboard.kilt.io

4. Change access from "allowed" to "denied"