Today I exposed the compiled muse_min.js library for Muse in my wallet repo and I am very happy with myself. You can refer to steem-js documentation for any implementation specifics.
Just use the consolebrowser.html file in your browser, PLEASE DO NOT USE YOUR REAL KEYS!!! Not safety tested!!!
FIND YOUR MUSE!
https://github.com/Tadasu85/Muse-Wallet
Enjoy!