In my experience it is simply necessary to prevent oxygen to get back into you jar, as oxygen is what is needed for mold to develop. In regards to pressure recommendations, I am not of much help, I like to use old preserving jars with a rubber band between jar and lid, that allowes pressure to get out without oxygen getting in.

I like to use Anki with some shared card decks: https://ankiweb.net/shared/decks?search=german

The learning pattern that Anki has configured by default suites me quite well and the app and the card deck is highly customizable.

Mind you, this is mostly only for learning vocabulary, not for learning grammer.

For me, it’s not the text placement itself but the mapping of color and text. Reddit should be red, Twitter should be blue 🧐

I don’t know where you got “a couple of years old” from. Do you mean, that the Fairphone 4 in general is a couple of years old?

Because, on the website it says the refurbished devices are: “After less than a month of Fairphoning, the phone is returned” So the Fairphone was only in use for max 4 weeks. I would still count that as mostly first hand :)