Close After Last Tab wót YK Leung

This is a Firefox extension to implement the Chrome-like behavior of closing last tab. So that if all tabs are closed, next time Firefox starts, the last tab of previous session will not be restored.

1. Please go to Options and set:
When Firefox starts: Show your windows and tabs from last time.
2. Go to about:config, set:
browser.tabs.closeWindowWithLastTab = false