If the problem is spying specifically, then build a proper sandbox for network traffic. Make sure the user knows if they want the sandbox disabled (or extensions seek specific permissions).
Like I said, there are many options here. Approval process should just do some automated scans but that's about it.
Such a sandbox can't be done for this use case. How would the sandbox know what is legitimate traffic for that extension and what is traffic related to spying?
Like I said, there are many options here. Approval process should just do some automated scans but that's about it.