Do you remember this slide? This was (and is) one of my most shared slides ever (from me, from third-party partners and also from Microsoft’s PTS team). This explained common problems on using per-tenant extensions on a SaaS environment:
Now things are changed and this slide must be updated (it’s overdue) 🙂
Starting from Dynamics 365 Business Central version 17, per-tenant extensions (PTE) are now tenant-isolated. In version 17, two PTEs with the same Id deployed to different tenants will no longer be in conflict. This means that you can install a PTE with the same Id and version on two different tenants now.
Obviously, you should remember a thing: two extensions must have the same Id ONLY if they’re really the same app, otherwise you should change the Id always (remember that telemetry and dependencies relies on the identity). But if you’re in the first case, now your life with PTEs is simplified a lot 🙂
Stefano Demiliani 
What’s your resource for this information?
Is this anywhere published on microsoft documentation?
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Not yet published I think, but you can just try by yourself 😉
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Hi Stefano,
Thanks for publishing regarding this matter. I initially missed this blog in december, but tested it now.
You stated, at least that’s how i read it, that the same app can now be used in multiple databases in multiple tenants. But how is that within a tenant when we have multiple production environments that can also be in the same region?
We currently still have a build pipeline to make different apps from one and the same app to deliver the exact same customization for the same customer with multiple databases in a tenant. The modification you wrote about could end this situation, which is a positive thing (leaving us with a job to do regarding data migration). I did a small test and it seems to work now to import the same app and even packages with a different package id’s (packaged multiple times) and the same version. That is however not what I expected, because within the same tenant the ‘old rules’ should apply, isn’t it?
So I’m a little bit confused now. Are there still restrictions within the tenant or are all restrictions lifted? I’m hoping you could shed some light.
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No, actually you can install the same PTE on different tenants and on different environments on the same tenant.
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Good news!
Thanks for your swift reply.
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