vicicarus wrote:I remember that I read that I needed some kind of PSN account to run the "Rejuvenate" but that service was discontinued/closed by Sony.
There are two PSM apps (the app you need to run rejuvenate) on the Vita:
1. One for PSM developer. This requires an account which is now impossible as you already stated. Plus the PSM app is not DRM free, so no way to install it on an older FW.
2. One for Unity developer. Luckily the PSM app for Unity is DRM free.
So the good news is that you can just download the PSM for Unity App and install it using the PKG installer (which is still available in 3.18). No need for an account. You have to use a very annoying email trick every day tho to 'activate' the app tho (the main reason I don't really use Rejuvenate).
vicicarus wrote:I guess my question should be if the tools to upgrade to a "better" FW are still available?
As for this second question, you can always upgrade your Vita to a higher FW (not necessarly the latest FW). You just need to 'emulate' your own update server instead of going to the official vita update server:
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