Don’t fret. I was the one reading quickly, leading to a misreading. Hence why I was able to spot my mistake upon re-reading your comment

Fretboard is for looking up chords, I reckon

Edit: nvm. Misread your comment as “looking up chords (guitar) on Flathub”

There’s Ambient Music Mod, “Port of Now Playing from Pixels to other Android devices”. It’s not the same, but it allows for your device to recognise popular music even while offline, possibly on a regular basis. It requires Shizuku, though.