Advanced settings by default is hidden. If you need to access advanced settings, press Ctrl + L while using the Launcher.
If you are on the Sign In screen, you will see a new link at the bottom of the Sign In window called "Advanced Settings."
Sign In Window with Advanced Settings Enabled
If you are signed in to the Launcher, you will see a new tab under the "Settings" window.
Settings Page with Advanced Settings Enabled
To hide the Advanced Settings tab, press Ctrl + L again to disable it.
Remember Me
If you would like to disable the "Remember Me" option entirely for anyone that uses the Launcher, you can enable "Disable 'Remember Me'" under the Settings > Advanced tab.
When enabled, the "Remember Me" checkbox on Sign In will be disabled by default