Hi Sallu Don,

You can turn on Autofill Logins and Passwords

• Click on menu bar.
• Click on Settings.
• Choose Privacy & Security from left menu and Tick Autofill Logins & Passwords from Logins & Passwords toolbar.

It is already ticked Shawshank.

Whenever I started the firefox, it would automatically login on any sites I wanted to surf in. But I am very disappointed that its not happening now at all. Morever tabs doesn't switch respective of use now. I feel like switching to Chrome now.

In case you use "Clear history when Firefox closes" or otherwise clear history.

• do not clear the Cookies
• do not clear the Site Preferences

• Settings -> Privacy & Security
  Firefox will: "Use custom settings for history":
  [X] "Clear history when Firefox closes" -> Settings
• https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox

• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exceptions for passwords and other website specific data
• clearing "Cookies" will remove all cookies including cookies with an allow exception you may want to keep

Detail like websites remembering you and log you in automatically is stored in a cookie.

You can use these steps to make a website recognize and remember you.

• create a cookie allow exception with the proper protocol (https:// or http://) to make a website remember you

You can check that you aren't clearing important cookies.

• using "Delete cookies and site data when Firefox is closed" keeps cookies with an allow exception
• using "Clear history when Firefox closes" to clear cookies clears all cookies including cookies with an allow exception you may want to keep
• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exceptions for passwords and other website specific data

• Settings -> Privacy & Security
  Cookies and Site Data: "Manage Exceptions/Permissions"