I have lots of Music in Apple Lossless format (Alac) which isn’t supported by Sailfish OS from scratch. There was a trick in the old forum (https://together.jolla.com/question/199018/how-to-install-gst-libav/), but that doesn’t work anymore - at least for me.
So first, this is a call for official support of Alac (and other missing Codecs) by default.
Second, it’s a call for help to get alac re-enabled. I had Alac running with the hints from the link above, but some weeks ago storeman offered gstreamer updates. I installed these, but finally killed my camera. Reinstalling the camera and updating necessary files from terminal brought the camera back but killed the former enabled alac support - this was (as said) once installed like described in the link above, but this procedure does not help any longer.