I am not aware of any changes in checked file sizes. But with only HTTP inspected, AMP is not really relevant nowadays.
For the TLS decryption: Yes, beta (or alpha?), and I would expect that Meraki will drop this feature in favour of the Umbrella SIG integration. But that is only a guess. And I don't want to imagine what happens to my MX64 after enabling the inspection. Probably it will just burn and cry because of missing resources ... 😉
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