K-9 is being used as the base for Thunderbird for Android but it isn’t there yet. FairEmail is a lot closer in functionality at the moment.

I use Thunderbird for Gmail (among other accounts) and it has to regularly compress my Gmail box, which none of the Android clients do - in my experience, Aqua Mail, K-9 and FairEmail all struggle with a decent sized Gmail mailbox after a while.

The one headphone adapter I have doesn’t seem to work, and I don’t think there was one with the phone. Finicky is probably right!

This 2022 Nokia has an FM radio. I had a look at the app and it says ‘Please plug in your headset to tune’. It’s not impossible that the USB C port is wired so wired headphones plugged in through an adaptor act as an aerial I suppose.