Nextcloud 10.0.2 on Ubuntu 16.04.1
Firefox works well, as well as Google Chrome and IE 11.
Chromium (Ubuntu 16.04) does not work for me
Opera on Ubuntu does not work
Opera on Windows does not work as well
Opera isn’t officially supported because Audio Player has not been tested with Opera.
In a short test with 41.0.2353.69 on Windows 7-64, Audio Player worked as expected. Some CSS problems still need to be fixed.
