If you have accounts on several Tenants or the Host, you can Link them together.
This allows you to switch between accounts and Tenants without having to logout, enter credentials, and login.
To manage Linked Accounts, open your user settings and click Manage Linked Accounts :
This opens the Linked accounts pop-up :
Link new account
To add a linked account, click Link new account.
Fill-in the form for the account you want to link to :
Removing a linked account
If you want to un-link an account, click the trash icon in front of it.
Login as linked account
To login to a linked account, click the Login button in front of it in the Linked accounts pop-up.
There is also a shortcut in your user settings :