How hard would it be to code a persistent bottom-bar audio player that replaces the per-card player? I have a music store app, and one of the drawbacks of an audio player on each card is that if you scroll a bit and find a new song you’d like to hear, while the old song is still playing, you’ll hear both songs at once. And that’s a pain, because now you have to scroll back up through the cards to find the card where you need to stop its player. A bottom-bar audio player would also enable a user to have finer control when scrubbing through a song. Might Softr develop this themselves anytime soon?
Cross-sharing my answer:
That’s quite a specific use case which is a great opportunity to try to achieve this with the vibe-coding block 
I shared some thoughts about when to use the vibe-coding block VS native blocks: When to use the Vibe Coding block vs. native blocks in Softr
Hope this helps
could you use css or javascript for this in a block?