USE MULTIPLE FACEBOOK A/c(s) IN SAME BROWSER
Google Chrome
1. Log in to your facebook a/c.
2. Right click on the Facebook home link present at the top left corner.
3. Choose open
link in incognito window.
DONE !
Mozilla Firefox
1. Log in to your facebook a/c.
2. Go to taskbar and right click on it.
3. Choose Open in Private Window.
DONE!