I generally lean towards the impersonal form in Italian. I think English can afford to use the personal form since it has the neutral gender (it), which is lacking in Italian. Using the personal form in Italian generally requires a gender to be defined. This is often arbitrary and in most cases just it doesn't feel right. Is Firefox a guy? Is Opera a lady? I don't know and I don't even want to care. Let's stay impersonal, whenever possible
Now, either using the impersonal or impersonal form, trying to literally translate English idioms is probably not doing any good. Idioms are meant to be translated with idioms, as long as the core meaning is preserved.
Let's take for instance the message
Crunching the latest data, just for you. Hang tight…
Any close-to-literal translation I can think of would be spectacularly awkward and it would indeed be an example of Doppiaggese.
If I were responsible for translating such a message, I would rather focus on
- meaning: data is being computed. It will take a few moments.
- tone: colloquial, almost playful
and try to convey both of them using Italian idioms, whenever possible, or just the meaning if the form cannot be preserved faithfully.
Stiamo elaborando i dati più recenti. Un attimo solo...
About the example:
- I decided to use stiamo and be somewhat personal, since the original message was very colloquial.
- I skipped the just for you as I couldn't think of a non-awkward translation. That's ok since the original meaning has been preserved, although some of the tone is being lost.
- Hang tight could be maybe translated with Tieniti forte, but its purpose in the original message is to transmit the information: "This is going to take a while. Please wait.", so I decide to go with a kind of plain (but still colloquial) Un attimo solo. Again I chose meaning over form.