VNC.js is a LinkedIn intern hackday 2011 2011 project, read the blog post about VNC.js: http://engineering.linkedin.com/javascript/vncjs-how-build-javascript-vnc-client-24-hour-hackday
You need a VNC server to make this work, like: x11vnc on Ubuntu.
You can change host in index.html ,e.x. localhost:1024, 192.168.8.100:5900
This project was developed over 24 sleep deprived hours, the code is messy and undocumented.
matchbox keyboard
sudo nano /usr/share/matchbox-keyboard/keyboard.xml
enable x11vnc
https://www.randomdevstuff.com/install-x11vnc-on-raspberrypi/
add imagetk apt-get install python3-pil.imagetk # Note that python3-pil installed as a dependency