Answer by spacebiker for How to get rid of Stayfocusd chrome extension?

Go to Preferences → Extensions, and from the list click remove (bin icon on the right)

If that does not help, you can try the following:

• On Windows 7: close Chrome and go to C:\Users\<username>\AppData\Local\Google\Chrome\User Data\Default\Extensions and remove the offending extension
• On Ubuntu 12.10 either:
  • go to /home/<username>/.config/google-chrome/Default/Extensions and remove the extension
  • Launch Chrome from the terminal with the -incognito (or --incognito?) flag and remove the extension