A web page can only read a file off this device if the browser opens a file chooser for it. Some in-app browsers — Fermata's among them — never implement one, so the button has nothing to open and the keyboard comes up instead. No change to this page can add a chooser to that browser.

What works instead is serving the folder over HTTP from this same device and loading it by address. A server on 127.0.0.1 is readable from an https page; a LAN address such as 192.168.1.5 is not. The server also has to send an Access-Control-Allow-Origin header, which most simple ones do not — tools/music-server.mjs in the Midio repository is a small one that does.

Opening this page in Chrome instead, where a chooser exists, also works.