I use Vanilla Music. It does folder play particularly in a way I want, where it adds the songs randomly into a queue, which shows me how many songs are left, lets me manually move them around, etc.
It also seems to have a lyrics search plugin, but I don't know if that means lyrics support in the way you want.
I would use multiple firefox profiles for this. If you go to
about:profiles
or use the commandfirefox -P
to launch firefox, you can view and create other firefox profiles. Each firefox profile is essentially it's own instance of firefox, complete with different history, extensions, and setting. You could have a "Netflix" profile and a regular browsing profile.