You can switch between primary accounts or between Google and Microsoft accounts by logging out and back in with the other account.
To log out from Timeless:
Go to the new tab page.
Click 'Preferences'.
Click 'Log out' [the bottom next to 'Account'].
To log back into Timeless, you'll need to reconnect with your account. See here how to.
Where do I see which account I am logged in with?
Go to the new tab page.
Click 'Preferences'.
Check the email address next to 'Account'.
