https://docs.sony.com/release/prst2.pdf (page 65) Yep, that's how it works from factory.
My question meant, is there another way to configure other size (f.e. size 8) to do that, instead of the 2nd? Mainly because I would like to read PDFs in the 2nd font size (since 1st to 3rd size means a big jump). Might have to root the device and find an android app that does that, but still hoping for a simpler solution to it without rooting...
Thank you!