Is this still an issue? MPD is running as root:dietpi, myMPD as mympd:dietpi.
Since we managed to have samba drives and several other software creating their files with 66X permissions, the shared dietpi group should allow full cross access.
Not sure, why we switched MPD back to root user. I opened a PR to revert this, adding some capabilities to the systemd unit from official one, that were perhaps missing in the past for full features. However it's the shared group that should guarantee cross access.
@naum
Did you setup the SSL key + certificate properly? Note that the mympd user or dietpi group need read access to those files, which is not the default, if you enabled SSL via LetsEncrypt.
Check myMPD and system logs for errors: journalctl -u mympd or journalctl -t mympd and I don't know if/where myMPD places it's log file(s)?
Another issue could be either browser or server side caching. Reload the page on the browser via pressing both: <ctrl>+<F5>
I guess you restarted myMPD service already after doing the change, as last resort try if a reboot helps.
And did you try it with different browsers?
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